Main content

Alert message

(this document is an excerpt from Report on the Computer Network Study Project (1999)


This chapter was written in response to a mandate from the 75th Texas Legislature to investigate the feasibility and cost-effectiveness of developing electronic textbooks that may be used by students who are blind or have other disabilities. The chapter is based on the work of a subcommittee of the Computer Network Study Project Advisory Committee established under Senate Bill 294, 75th Texas Legislature. Committee members are listed in Appendix A.

This chapter discusses the recent changes in the state textbook adoption program that shifted from sole reliance on traditional, print-based textbooks to a wide variety of instructional media. These recently available formats include, but are not limited to computer software, compact disks (CD-ROM), videotapes, interactive videodiscs, and instructional materials downloaded from the Internet or the various online services. Historically, copies of the traditional textbooks were produced in braille, large print, or audiotapes to be accessible to students who are blind or visually impaired. However, the new instructional media formats cannot easily be made accessible to students with disabilities.

The most common components of electronic textbooks that should be made accessible to students and teachers who have disabilities are described in the report. The report also summarizes the types of information and delivery modes that must be made accessible and analyzes how these electronic textbooks can be made more accessible to all students in addition to students and teachers with disabilities.

Specific recommendations are included in the report. (1) These encompass design and implementation of demonstration projects to develop accessible electronic textbooks; (2) collaboration with experts in media accessibility research, textbook publishers, software and hardware developers, and educators to develop minimum accessibility standards for new interactive electronic textbooks purchased by the state of Texas.


In 1989, the 71st Texas Legislature amended the textbook adoption process to include electronic media. The expansion of the definition of "textbook" to include product configurations that encompassed new technology led to the submission of a variety of multimedia instructional materials for state adoption. In subsequent years, instructional materials were submitted in configurations that ranged from teacher components only to more traditional student and teacher components, in print or electronic format, or in electronic format with supplemental teacher and student material in print format. Electronic components in many state-adopted programs include computer diskettes, CD-ROM, audio and videocassettes, and laser discs. More recently, access to the Internet and online providers has expanded rapidly as have opportunities to receive educational programming and distance learning via satellite.

The Texas Education Agency has a long history of providing equal access to state-adopted instructional materials for students who are blind or visually impaired. Since 1955, the agency has worked with various organizations to acquire textbooks in braille. With emerging technology, the process of acquiring braille evolved from primarily manual production to electronic production using publisher-provided computer files specifically formatted for more rapid translation into braille textbooks.

In 1991, the 72nd Texas Legislature required publishers of textbooks adopted by the State Board of Education to furnish the agency with computerized textbook files for the production of braille textbooks. The Legislature also mandated formation of a commission to work with textbook publishers on developing processes for converting publisher textbook files into formats needed for speedy braille production. In March 1993, this commission made a series of recommendations for revisions to the process of braille textbook production. Subsequently, the agency expanded the list of content areas for which textbooks could be brailled electronically to include all literary subjects in English and other languages. Currently, music and mathematics are exempt from this list due to technical complications that arise in brailling these subjects. Files supplied by the publishers were standardized and the minimum standards for these file formats were established.

Also in 1991, a videodisc-based program called Windows on Science became the first state-adopted electronic textbook in the nation. It was followed in 1992 by three electronic programs from as many educational publishers in the area of computer literacy, a required, full-year course at grade seven or eight. Each of these three programs included computer diskettes for Apple, Macintosh, or MS-DOS computers, integrated commercial software, laser discs or videotapes, and printed ancillaries. Subsequent electronic programs have been adopted in chemistry, science and world geography, accounting, economics, and other subject areas.

While expanding the range of learning opportunities for students capable of using the visual and audio features, electronic textbooks present new challenges to educators of students with visual impairments or blindness. Articulation of the major challenges and a series of recommendations to address them comprise the body of this chapter.

Accessibility of Information

Accessibility refers to the freedom or ability of an individual to obtain or make full use of a product or environment. A product is accessible to an individual with disabilities only if he or she is able to use it to carry out all of the same functions and to achieve the same results as individuals with similar skills and training who do not have disabilities.

Electronic Textbooks

The Texas Education Code defines electronic textbook as "computer software, interactive videodisc, magnetic media, CD-ROM, computer courseware, online services, an electronic medium, or other means of conveying information to the student or otherwise contributing to the learning process through electronic means " [Sec. 31.002 (1)]." This definition defines only the physical delivery media (e.g., computer software, CD-ROM, and online services). The delivery medium is not inherently inaccessible to students with disabilities. The critical features of the electronic textbook are the content and the method of presentation of that content.

The design and presentation content within a textbook, the delivery medium, determines if 10 the information is accessible, 2) all students can learn from the content, and 3) it is usable by all students. Although, information on the Web and on the Internet can be made accessible, the accessibility of many current materials delivered through this media is questionable. This is a critical issue that must be considered as the state investigates the cost and benefits of using computer networks, including the Internet and Web in public schools, and receiving textbook updates via the Internet.

World Wide Web Consortium

The World Wide Web Consortium is an international industry consortium founded in 1994. Its mission is to promote the evolution and ensure the interoperability of the World Wide Web. Working with the global community the Consortium produces specifications and reference software for free use around the world. The World Wide Web Consortium's commitment to Web accessibility is shown in the following activity statement: "All the protocols and languages we (the W3C) issue as recommendations should meet or exceed established accessibility goals. In addition, we will actively encourage the development of Web software and content that is accessible to people with most disabilities."

To meet this commitment and develop accessibility goals, the World Wide Web Consortium established the Web Accessibility Initiative (WAI) in 1997. Changing the Web's underlying protocols, applications and, most importantly, the way content is developed can significantly improve access to the Web by people with disabilities. The WAI has working groups developing comprehensive and unified sets of accessibility guidelines for browser accessibility, authoring tool accessibility, and page design (presentation of content).

"The power of the Web is in its universality. Access by everyone regardless of disability is an essential aspect," said Tim Berners-Lee, W3C Director and inventor of the World Wide Web.

In order to provide an overview of the global nature of the Web and the need for accessibility the following is excerpted from the "Briefing Package for Project Web Accessibility Initiative" (

"The emergence of the World Wide Web has made it possible for individuals with appropriate computer and telecommunications equipment to interact as never before. The Web is the stepping stone, the infrastructure, which will pave the way for next generation interfaces. Part of the W3C's commitment to realize the full potential of the Web is to promote a high degree of usability for people with disabilities.

The current situation in that area is not very good and is getting worse every day as more and more people rush into the Web business without any awareness of the new limitations and frontiers they may create. No single disability population is unaffected.

For example:

  • People who are deaf cannot hear multimedia or audio events that do not contain captioning.
  • People who are blind struggle with the Web's inherent graphical interface, its graphic-based content, and any Web protocol or application that cannot easily be rendered or accessed using audio, braille, large text or synthetic voice.
  • People who are physically challenged have difficulty using certain hardware devices or web controls, including Web kiosks and WebTV.
  • People who are cognitively and visually impaired have difficulties interpreting most web pages because they have not been designed with this population in mind.
  • Worldwide, there are more than 750 million people with disabilities. A significant percentage of that population is affected by the emergence of the Web, directly or indirectly. For those without disabilities, the Web is a new technology that can help unify geographically dispersed groups. But these barriers put the Web in danger of disenfranchising people with disabilities in this emerging infrastructure. Furthermore, even those without disabilities would benefit from many changes motivated by the needs of people with disabilities. When driving a car, for example, the driver may wish to browse the Web for information (movie schedules, etc.) using a voice-based interface similar to that used by the blind."

The Need for Accessible Electronic Textbooks

Consider these common classroom uses of technology:

  • Elementary science students watch a videodisc of an experiment being performed.
  • Middle school students manipulate commercial software applications that prepare them to use rapidly changing technology in the workplace and in the society at large.
  • High school students learn about thermodynamics through a full-motion video segment recorded on a CD-ROM, then play interactive chemistry "games" on the Web that score their manipulation of chemical equations and formulas to solve real-life problems.

Now, focus on the students who have disabilities in these same classrooms:

  • A child who is blind cannot see the videodisc presentation of the experiment being performed in the elementary science classroom. There are no audible descriptions to allow him or her neither to grasp the step-by-step procedures nor to see their results. He or she cannot participate in this portion of the instruction.
  • Middle school students who are physically impaired are unable to complete the assigned computer activities because the commercial software is not compatible with available adaptive devices that would permit the student to independently participate in and complete the task.
  • High school students who are hearing impaired cannot make use of the CD-ROM or web-based full-motion video unit on thermodynamics because they cannot hear the information that is presented. Because captions were not included in the video, they are excluded from acquiring the information presented.

Each of these hypothetical scenarios demonstrates the need for accessible electronic textbooks for all students. Obvious benefits are that the students will:

  • Perceive the information for which they could be held accountable.
  • Respond to information in the textbooks and interact with the information on a variety of levels.
  • Learn from the information.

An accessible electronic textbook is one that allows students who have disabilities to use the same textbook and achieve the same intended benefit as students who do not have disabilities. Moreover, they would be able to achieve the benefit with approximately the same amount of effort. At a minimum, that means that the electronic textbooks should be:

  • Perceivable. The information that is presented in the book must be available in a form that can be perceived by the student. For example, if the student is blind then all of the information that is presented visually in the book should be available in another form such as audio that the student can use.
  • Operable and Navigable. Students should be able to orient themselves and move within the electronic textbook. For example, a student has difficulty with eye-hand coordination (because of injury or disability). The student uses an electronic textbook, which requires a mouse or other pointing device to activate controls or navigation aids. Without an alternate means for navigating the control such as voice or keyboard control the student would be unable to use the textbook.
  • Functional. The textbook should provide the same function or benefit to the individual with a disability as it would to other students.

Which Textbooks Should Be Made Accessible?

Ideally, all electronic instructional materials should be made accessible to all students, including those with disabilities. All students have different functional abilities and learning styles. Each requires a variety of learning experiences to maximize learning. Providing all students instructional materials that present information in an enriched and multimedia environment allow each student to interact with the materials in a manner that best fits the individual's learning mode. Not all students can read printed material; not all students can hear audio information; and not all students can comprehend complex diagrams. However, in a multimedia environment, the information in print can be provided in audio; audio information can be captioned and displayed in print; and complex information can be displayed as a simplified series of diagrams building to create the complex diagram. Different students learn differently. The same presentation of material that makes sense to one student may be meaningless to another. A multimedia instructional environment would allow students to choose the presentation mode of the material that works best for them.

There is no one tool or medium that provides all students with all the information needed to learn well. If the textbook presentation does not provide information that is meaningful to the student, then classroom teachers, disability specific teachers, and other professionals should provide an equivalent that meets the learning goals and provides equivalent information. Passive relaying of the information is not enough when other students are obtaining the information actively.

An accessible electronic textbook might teach the concept of the piston engine by presenting a visual simulation of a model four-stroke engine. The user can manipulate the components by using a touchscreen, keyboard commands, or a mouse to grab the flywheel and turn it left and right in order to see how the pistons operate. A tone is associated with the position of the piston; as the individual used the arrow keys to rotate the flywheel, a rising tone would indicate the rising visual position of the piston. The student could hear the piston going up until the sound of an explosion was heard at the same time that the visual simulation of the spark is given. The student would then hear the piston tone going back down. In a four-cycle engine, they could hear the valves opening and the piston going up without an explosion, the exhaust valve closing as the intake valve opens. The auditory sounds could be accompanied with a simple narration (accompanied by captions) of the events as they were happening.

Electronic textbooks can be made accessible through changes to the software used to present them. Details of how to make these changes are included in this report. However, some students with disabilities may require a more comprehensive instructional approach which includes non-electronic textbook materials. Using the accessible electronic textbook with the adaptations described above, a student who is blind may not achieve the same benefit as the other students. For him or her, an unintended outcome might be that a flywheel is thought of as a left/right button. The noises may have no meaning unless they were the same as those coming from a real piston engine that the student has directly touched and manipulated. No student could learn the concepts associated with a piston engine only with noises and verbal descriptions. Some students may need additional hands-on interaction with physical models to more fully grasp the concepts. A model would be crucial to the understanding of students with visual impairments and would probably be beneficial for other students as well. Additional instruction might be needed from a teacher trained in the education of students with visual impairments to ensure that the information is absorbed in a non-visual way.

Students with other disabilities or learning styles might benefit from a series of diagrams provided in the electronic textbook that could be printed and reviewed at a later time. The electronic textbook could provide also links to other resources on the Web to ensure that students with a variety of learning styles can connect to the material.

What Must Be Made Accessible?

The critical features of the electronic textbook are the content and the method of presentation of that content. The design and development of the content and its presentation within a textbook determines the its usability, the accessibility of information, and the students' ability to learn from the materials. If the electronic textbooks are not properly designed, the electronic textbook will be partially or completely inaccessible and unusable by students who are blind, have hearing impairments, or other disabilities.

In order to discuss accessible instructional delivery media and systems, it is useful to provide a common frame of reference. Many of the delivery media have common design and formatting elements that must be made accessible. It is important to contrast each element of traditional print textbooks with the elements of electronic textbooks. The print textbook is an information delivery system with which most people are familiar and, therefore, is used as a point of reference in this section.

A print textbook is made up of the following formatting and design elements:

  • Text. The unformatted words and punctuation that make up the document.
  • Text Formatting. All of the attributes of characters and words, such as bold, italics, underline, colored lettering, or size. These attributes provide the reader with additional information, such as identifying words that are new terms or the name of an important person, so that the print textbook is not just a random collection of words. The words are structured into meaningful units, such as sentences, paragraphs, pages, sections, and chapters, as well as tables and lists.
  • Symbolic Text. All subject-specific, semantically rich symbol sets, related text, and positioning, such as mathematics symbols, chemistry and physics notations, and others. These symbols and their position in relation to each other provide the reader subject- specific information and meaning, so that an equation or geometric proof is not just a meaningless pattern of symbols. Depending on the subject, such as mathematics, chemistry, or physics, the same symbol may have different meanings.
  • Graphics. Photographs, maps, charts, graphs, illustrations, and diagrams. These may have text associated with them, as with captions, or contain text embedded within the graphic itself.
  • Navigation System. Formatting and design elements include color sidebars, a table of contents, different levels of headings (chapter, section, subsection), indices, and page numbers. These navigation systems help the student find specific information (text or graphic) in a print textbook.

Electronic textbooks are made up of these same formatting and design elements as print textbooks, text formatting, symbolic text, graphics, and a navigation system. These formatting and design elements are enhanced because the information is presented electronically.

  • Text. Text in electronic textbooks may be resized, or the font may be changed to meet the reader's needs.
  • Text Formatting. In addition to all of the attributes of printed textbooks, text formatting in electronic textbooks may include hyperlinks which can move the reader to other parts of the page or book (see Navigation System below).
  • Symbolic Text. Symbolic text in electronic textbooks may be resized or reformatted to meet the reader's needs. The student may be able to move symbols or edit equations to solve problems. The resulting solution could be dynamically graphed or displayed for additional student interaction.
  • Graphics. The electronic versions of graphics may allow the image to be expanded to fill the entire screen, or sections of the image could be expanded to show detail. Graphs and charts may dynamically change to reflect student interaction or manipulation of associated data.
  • Navigation System. Electronic textbooks use techniques for finding specific information within them, such as navigational maps, tables of contents with hyperlinks, heading levels, indices, and page numbers. They may also include hyperlinks, expand and collapse features, search functions, and interactive controls for navigating and controlling the information presentation.

Electronic textbooks may also include the following elements, which are not typical of print textbooks:

  • Hyperlink. A hyperlink is a segment of text (word or phrase), or an inline image (an image displayed as part of a document) which refers to a location within the current document, or another document (i.e., text, sound, image or movie) elsewhere on the Web. When a hyperlink is activated or selected, the referenced document is retrieved from the Web and is displayed appropriately. The electronic textbook may also include a "search" feature to find a specific word or phrase anywhere in the book. These navigation systems help the student find specific information (text, graphic, movie, or activity) in the electronic textbook.
  • Expand and Collapse Features. Electronic textbooks also have the ability to expand or collapse their structure. For example, it is possible to produce a document which would collapse down to its major titles and subtitles. This makes it much easier to see the overall structure and to navigate to a particular level in the structure. Once that point is reached, it is possible to expand the structure exposing all of the paragraphs at that point. It is also possible to produce a document which provides a cursory treatment of all of the material, but which allows the student to expand the information presented at any point in the document if he or she requires additional information.
  • Search Features. Search features provide users with the ability to search documents and to jump immediately to any occurrence of a particular word or phrase which is used. This capability also includes a "fuzzy" search capability, which allows an individual to search, for example, for the word "fish" and automatically find occurrences of the word "fish," "fishing," "mackerel," "trout," and "perch."
  • Sound. Examples of this auditory information include prompts or warning sounds, music, spoken words, and natural sounds such as a lion's roar.
  • Fixed Sequence Animation and Movies. Electronic textbooks may contain moving graphics. These may take the form of a simple diagrammatic animation or a full-color, high-resolution, graphic movie that may or may not be accompanied by sound.
  • Interactive Elements. Electronic textbooks may contain visual graphic animation or symbolic interaction that can be controlled and manipulated by the student. In the example presented earlier, it is possible to show a four-stroke engine where the student can actually turn the flywheel on the engine. The student could explore by moving the flywheel controls forward and backwards at different speeds, study all of the workings of the engine, including the timing of the various events and mechanisms. More sophisticated simulations even allow students to carry out chemistry experiments where beakers, flasks, burners, and other apparatuses are manipulated on screen and the chemical reactions (e.g., color changes, heating, and explosions) occur on screen as they would if the real items had been manipulated. On a symbolic level, students could interactively change values in an equation describing the lift properties of an airplane wing, and see how the wing changes shape and its effect on the flying ability of the airplane.
  • Live Information. Electronic textbooks may contain hyperlinks to the Web that would provide students access to live information. For example, a science textbook could provide links to live weather information; a unit on volcanoes in a geography textbook could link to live seismographic information; or a biology textbook could link to "Chickscope," a live view of chicken embryo development within an egg.
  • Collaborative Environments. Increasingly, education is becoming more collaborative. An electronic textbook could be designed giving students the ability to collaborate, through the use of "chat rooms", e-mail, discussion forums, or videoconferences. Students would be able to study with peers or a team to write reports, share research data, or share a "white board" or area of the screen where they can draw, write, calculate, or otherwise work together on the same "piece of paper." Through modern telecommunications, live people may be embedded in electronic textbooks. For example, touching an image in the electronic textbook would cause a communication link to be opened with a person - the teacher, other students, or perhaps a resource person somewhere else in the world studying a similar topic. The student would then be able to ask questions or interact with that individual. Essentially, a video teleconferencing session could be opened between the student and the teacher or resource person.
  • Three-Dimensional or Immersive Environments. An electronic textbook may include an immersive, three-dimensional environment or experience (commonly referred to as virtual reality). Depending on the rendering, these environments can be viewed, heard, felt and/or manipulated using various stereoscopic displays, three dimensional sound systems, haptic interfaces and/or three dimensional controllers. Ideally these environments should simulate real world experiences without real world constraints. These simulated environments are used:
    • to replicate experiential learning, or practical demonstrations (e.g., a risk-free chemistry lab);
    • to allow the student to explore "what if" scenarios (e.g., what if we reduced the earth's gravitational pull);
    • to allow the student to experience otherwise impossible points of view (e.g., the backyard from the point of view of an ant);
    • to allow the examination and manipulation of simulated three dimensional objects, which can be resized to suit the learning experience (e.g., viewing the heart from all sides or viewing a complex protein molecule);
    • to assist students in visualizing and understanding complex data that are not inherently visual or spatial (e.g., demographic effects of global warming on the Texas economy);
To fully realize the potential of immersive experiences, classrooms require major enhancements to computer workstations, including enhancements to available display technologies, control technologies, processing power, and communication bandwidth.

Direct Accessibility Compared to Compatibility with Add-on Assistive Technology Devices

In discussing access to electronic textbooks, it is useful to use the terminology and approach which has been adopted in the Telecommunications Act of 1996, Public Law 104-104. This Act refers to accessibility as the ability of individuals to directly use telecommunication products without requiring special assistive devices (i.e., devices designed to meet the needs of individuals with disabilities). The Act states that telecommunication products and services should be made accessible if this is readily achievable. The Act states that if it is not readily achievable to make products accessible, the telecommunication products and services should be compatible with existing peripheral devices or specialized equipment commonly used by individuals with disabilities to achieve access, if readily achievable. Because there is a close parallel between telecommunications software and electronic textbooks, parallel terminology is used here as follows.

  • Direct or Built-In Accessibility. The ability to use an electronic textbook without the use of separate assistive technology devices. In essence, for a product to be directly accessible, the needed capabilities would have to be built into the product rather than relying on add-ons.
  • Compatibility with Assistive Technology Devices. The ability of an electronic textbook to be used in conjunction with standard assistive technology devices used by people who have disabilities.

The Telecommunications Act of 1996 shows a clear preference for having direct or built-in accessibility for telecommunication products and services. However, each approach has advantages. Electronic textbooks should be directly accessible to the vast majority of students with disabilities and be compatible with assistive technology to meet the specialized needs of some students with disabilities. This will provide the advantages of both approaches.

Advantages of Direct or Built-In Accessibility

  • Cost. Direct accessibility has advantages in cost, availability, and inclusiveness. When products are directly accessible to a student, schools do not need to deal with the added expense of acquiring special assistive devices to access and use the electronic textbook. Given the rapid changes in technologies, this also means that schools would not need to continuously buy new assistive devices as electronic textbooks evolved. Additionally, a directly accessible electronic textbook provides an enriched learning experience for all students.
  • Hardware Independence. When accessibility is built in, students do not need to worry about whether their assistive technology will work with a particular computer. Today, electronic textbooks are available in a limited number of formats. However, in the future, it is likely that electronic textbooks will be produced in a wide variety of hardware and software formats, making it difficult for a user to have all of the right assistive devices or adapters. Also, students may encounter electronic textbook technologies in the library, in laboratories, and in different classrooms, meaning every computer location would need assistive technology installed. Or the students would have to always have their assistive devices with them and these devices would have to be compatible with the various hardware and software platforms encountered.
  • Inclusiveness. By using the same textbook and learning environments all students will have increased interaction and collaboration with their peers. When students with a disability can directly use the same electronic textbooks and equipment, it is easier for them to work side by side with their peers who do not have disabilities. Students could use any textbook or textbook viewer/work station at which they and their partners sit, rather than having to work at specially adapted stations which may not be in the same location or which may not be usable or usable at the same time by their peers without disabilities.
  • Intuitiveness. When access is built into electronic textbooks, it generally provides better and more intuitive learning experiences for the student with disabilities. Once the textbook has been opened, all of its functions should be usable without assistance. This is particularly important for students who are blind, or have other disabilities, especially in grades K-5, where mastering the instructional goals of the textbooks and learning to use other adaptive devices simultaneously would present a much higher cognitive load. Learning and interacting with the content should not compete with learning how to use and configure assistive technology with the electronic books.

Advantages of Access via Assistive Technology Devices

Where it is impractical on a cost basis to have built-in assistive technology hardware and specialized software, compatibility with standard assistive devices has advantages.

  • Power. At the present time, the most powerful and well-developed user interfaces (i.e., the parts of a computer program that can be seen or heard by users) for many disabilities, including blindness, are those that have been developed by assistive technology manufacturers. Some devices are very powerful, but it would be difficult to build them directly into electronic textbooks. For example, use of dynamic braille displays (i.e., computer-driven electro-mechanical devices which display braille symbols with small prongs, pins or other means and allow the braille to be changed as each line of text is presented) or printed braille are very powerful access strategies for individuals who know braille. However, it is unlikely that it will ever be economically feasible to build braille printing capability into standard printers or dynamic braille displays into electronic textbooks.

    Compatibility would allow schools to provide devices to students who would benefit from additional access to information in the electronic textbook. Individuals with multiple disabilities, such as those with visual and hearing impairments, would need to use interfaces. Other compatible assistive technologies that could be used to access the content of electronic textbooks include adaptive keyboards, specialized mouse or other pointing devices, speech recognition software, text to sign language converters, and raised line drawing printers.
  • Possible Standardization. If a single user interface is agreed upon by all textbook publishers and designated for access to all electronic textbooks, students with disabilities would benefit greatly. All electronic textbooks could then present information in a standard format that would be compatible with many popular assistive technology devices.

For these reasons it is important that direct accessibility supplemented by compatibility with assistive devices be considered in the design of electronic textbooks.

Strategies for Making Electronic Textbooks Accessible

Accessible electronic textbooks can take many forms. Each has different advantages and poses different accessibility opportunities and issues. There are, however, some general strategies that apply across most electronic textbook formats. The following sections describe some examples of the various formats of electronic textbooks, general accessibility guidelines pertaining to students with disabilities, and issues related to compatibility between common assistive devices and electronic textbooks.

Variety of Formats and Media

Electronic textbooks may be produced in many different formats. For example, it is possible to deliver a standard movie either as a VHS videocassette, as a videodisc, in digital form on a digital videodisc (DVD), or as a digital file which is downloaded or played live from the Internet. When viewed, the users would have no idea whether they were looking at videotape, a videodisc, or a file from the Internet. Similarly, an interactive textbook might be delivered to the school on a DVD disc, on a CD-ROM, or over the Internet or Internet-like communications link within a single school district (i.e., an Intranet).

Regardless of the format in which an electronic textbook is produced, the basic considerations for making it accessible are the same. Some of the delivery formats lend themselves to including accessibility features more than others.

Accessibility Requirements for Electronic Textbooks

Implementing these basic accessibility requirements provides students with disabilities access to the content in electronic textbooks. Following these requirements also presents content in a variety of media allowing all students with different learning styles, language and reading abilities, and functional abilities to gain meaning from the textbook. Additionally, the requirements allow a greater flexibility of access for all students, including the ability to operate the textbooks more easily in very noisy environments or in very quiet environments. It is not necessary to limit textbooks and other instructional materials to only a presentation of the text in order to make it accessible. Strategies and tools exist for making even rich multimedia and interactive systems accessible.

The basic accessibility requirements for electronic textbooks are:

  • All electronic textbooks that are delivered via the Web must follow the content design principles established by the World Wide Web Consortium's Web Accessibility Initiative (WAI) Guidelines, including, but not limited to, WAI Page Author Guidelines, WAI User Agent Guidelines, and WAI Authoring Tool Guidelines.
  • Use system tools whenever possible, including standard controls and standard text drawing routines. When this is not possible, use operating system tools (such as Microsoft Active Accessibility) to provide similar usability.
  • All important information presented visually should also be available to the user in both auditory and text form. "Human voice" should be considered over synthesized speech whenever possible.
  • All important information presented in audio must also be available in visual form. This should be provided as closed captions (with an indication of environmental sounds) and should include a text transcript. Movies could contain an optional sign language track.
  • All important video or animated presentations should include audio descriptions of visual information for use by blind and visually impaired users. Including the text of the description for review would also be useful.
  • Electronic textbooks should have the capability for increasing or reducing the speed of presentation, or pausing the presentation, to allow for different levels of comprehension.
  • All controls should be operable in an efficient manner without a pointing device (e.g., a mouse). Providing keyboard commands for all important functions will support users who cannot use a mouse or who use alternative input devices, including speech recognition.
  • All text should be user adjustable for font, size, and color.
  • Users should be able to zoom in to view portions of the screen in more detail.
  • Use established "standard" encoding such as Hyper Text Markup Language (HTML) and Extensible Markup Language (XML) for text; Graphics Interchange Format (GIF) and Joint Photographic Expert Group (JPEG) format for images; WAVE, QuickTime, Moving Picture Expert Group (MPEG), and Audio Visual Interleave (AVI) format for sound and video; and Synchronized Multimedia Interchange Language (SMIL) for sound, video, image, and text integration.

Compatibility Guidelines

An electronic textbook without built-in accessibility should be compatible with common assistive devices and software used by people with disabilities. The effectiveness of assistive technologies providing access to an electronic textbook depends upon the design and compatibility of the electronic textbook. Information that is not available in text form, for example, cannot be displayed using speech or braille. Software that requires an individual to simultaneously monitor two events occurring at opposite edges of a screen would be difficult for someone to operate by using screen magnification.

Accessibility of the Major Components of Electronic Textbooks

This section will look more closely at each of the major components of electronic textbooks presented earlier and discuss the implications of making each of these accessible.


There are two ways to provide the text content of an electronic textbook - through the visual interface of the book itself, or in companion files.

  • Text in the Visual Interface. There are two ways to visually display text in electronic textbooks. These are Standard Text Draw and Proprietary Text Draw. In the former, the electronic textbook uses the text writing routines of the operating system to draw text to the screen. In the later, the electronic textbook uses a text drawing method that needs software to translate it into an image. This includes what is commonly referred to as "bitmap text" - including text within an "image" file format that draws the text as a series of pixels rather than using the text writing routines of the operating system. Both methods for displaying text -- standard, or proprietary -- may be used to create animated text. Animated Text refers to text that is presented as a moving object or scrolled like a marquee.Animated text may cause a couple of different types of problems for students with cognitive disabilities. The student may not be able to read the text fast enough before it changes, or the animation may draw their attention away from the rest of the information being presented.Three methods are used to make text accessible in the visual interface. These are as follows:
    1. Synthesizing Speech from the User's End. Electronic textbooks that use standard text drawing are compatible with standard screen reading software. Care must be taken, however, to ensure that the information is written to the screen in such a way that the individual can make sense of it using a screen reader. Screen readers typically scan horizontally across the screen. Since screen readers try their best to keep the user up to date with changes on the screen, when standard text drawing methods are used, a screen reader will read the phrase that is changing each time it changes. For a marquee, this means that each letter is spoken once it appears on the screen.Electronic textbooks that use proprietary text drawing such as bit-mapped imaging are often not compatible with today's screen readers. Electronic textbooks that use these strategies must use either built-in accessibility methods or use programmatic strategies (such as Microsoft Active Accessibility, access features within HTML 4.0, or the Java Accessibility API) to provide the screen reading software with the appropriate information.Some data formats, such as Portable Document Format (PDF), intermix standard text drawing, and proprietary text drawing when writing text to the screen. If the operating system is knowledgeable about the specialized fonts used in a document, the PDF reader will use standard text draw. If the fonts are not available to the operating system, the reader will use its proprietary screen drawing routines to simulate the appearance of the font. This means that only parts of the text are accessible and this is not acceptable.
    2. Building Audio into the Textbook. When audio is provided with the textbook, there are fewer problems. With built-in accessibility, the same program that writes the text to the screen also provides the information in an auditory form, such as speech. However, if the audio presents information that is not available visually, it needs to be captioned or presented in some other visual form for students who are deaf or have hearing impairments. For students with visual and hearing impairments, the information needs to be available in text so that it may be presented using a dynamic braille display, as described above. Built-in accessibility should also allow the individual to move about in the text by section, paragraph, sentence, and word, as well as allowing the words to be spelled. These functions are available via most screen readers and emulate how a person with sight scans through a document "in chunks."
    3. Screen Magnifiers. Screen magnifiers are similar to screen readers in that they do not treat text in proprietary formats as text, but as "images." Therefore, when proprietary formats are used to create text, once magnified, the image may become grainy and unreadable. When standard text drawing is used, the size of the text that is drawn to the screen is increased and the text is displayed in a larger font, maintaining its clarity. Care must be taken in creating the layout of the information to ensure that it is comprehensible to someone who is able to view only a small portion of the screen at any point in time. A quick test is to try to operate the electronic textbook one word at a time (to simulate the portion of the screen available to a screen reader) or through the hole in a roll of paper towels (to simulate a screen magnifier).
  • Text in Companion Files. In addition to providing access to the information from within the electronic textbook, it is sometimes possible for publishers to provide techniques for extracting information and presenting it as separate or companion text files. This text file could then be used in conjunction with a word processor and screen reader or some other text-to-speech converter. An external representation of the text in an electronic textbook may be achieved in two ways:
    1. From the publisher. The publisher of the electronic textbook provides an alternate form of the electronic textbook as an American Standard Code for Information Interchange (ASCII) or other accessible text file.
    2. Extraction. The publisher of the electronic textbook, or a third party, provides a tool that extracts the information from the electronic textbook and stores it as an accessible text file. When such an extraction tool is used, it is important that all of the information that is conveyed in layout and formatting (e.g., bold, italic and titles) be preserved, along with navigational aids (table of contents, indices, page references, and hyperlinks). This approach is only viable for linear, static electronic textbooks composed primarily of text, and that have text equivalents of any graphical or auditory information. For example, it does not work on material where the user can take any one of a large number of paths through the material or interact with a simulation.

Text Formatting and Hierarchy

Text formatting and hierarchy is important because it provides information about the structure of the information and access additional layers of information such as emphasis and keywords. Text formats identify relationships between one text element and another, highlight key words, identify a sequence of presentation, provide information about the hierarchy of information, and provide other secondary levels of information to the reader. Making information about text formatting and text hierarchy available can be done in several ways, including:

  • Verbal tags: For example, "begin bold," "end bold," "Level 1 title," and "Chapter header," which are embedded in the text and/or spoken when the formatting is encountered in the text.
  • Some type of tonal cues could be provided when various formatting occurs. This could take the form of beeps or tones immediately preceding the words.
  • Background noise which is played while the specially formatted text is being presented or read.
  • Change in intonation or voice: For example, italicized words could be spoken with a different voice, at a different pitch, or at a different volume.

Of these approaches, only the verbal tag approach would work with information that is exported to a dynamic braille display. For spoken output, the other approaches may be less disruptive, but will become more effective as techniques that relate specific auditory cues to specific text formatting features are developed.

As discussed under Text, systems with built-in accessibility have an advantage in that they are sensitive to any special formatting which is built into the text being presented and are able to present this information. Systems that rely on external assistive technologies for providing access to the formatting information must use the standard system tools for formatting text so that they will be compatible with the screen readers. Some types of formatting and text hierarchy, however, may be difficult to present in a fashion that screen readers would be able to use or recognize and convey.

Symbolic Information in Text

Current symbolic text representation consists of displaying the equations or text as a graphic of the actual equation. Therefore, access to a symbolic (i.e., mathematical, chemical, or economic) equation in electronic media has traditionally been difficult for students who are blind or visually impaired. Some specialized systems for reading mathematical documents have been developed, but no method for reading mathematics in common educational software is available.

The recent approval of Mathematics Mark-up Language (MathML) by the World Wide Web Consortium offers a positive step. MathML was created to meet the needs of people who want to display mathematical expressions on the Web, but who were unable to do so using HTML. It defines a machine-to-machine language for expressing mathematical symbols; that is, people are expected to use authoring tools to create the MathML code and to use a browser of some kind to read it. Reading the code itself does not convey the mathematical symbology to a human.

The MathML code provides a standardized format for encoding mathematical equations that is independent of the final presentation media, be it print, audio, or braille. Rather than using complicated typographic conventions, or even graphic images, to represent equations, MathML retains the semantics of the equation, thereby allowing assistive technology or auditory interfaces to navigate the elements of the equation. This is a major step in accessibility. MathML also provides advantages in terms of visual display and potential synchronization of mathematical equations with other media, such as narration, and brings mathematics to life.

For example, a complicated equation is displayed on the computer screen or a web page. A narrator describes the equation and a highlight or color change follows the narration through each element (or group of elements). As a student points, using a mouse or keyboard, at one of the elements, it is spoken. With an additional mouse click or keystroke the element of the equation is expanded to show additional information about the element, such as how that element was derived, the part of the word problem to which it refers, or the part of a diagram it represents. All of this is accomplished in an accessible manner and interactively.

MathML can be used to create symbolic text documents (i.e., mathematics, science, chemistry, and economics texts will include mathematical equations) that are presentable via the Web or other means. These documents would be accessible to blind and visually impaired students once the tools needed to do so are available. This would include authoring tools for writing equations that are designed to be directly or compatibly accessible so that blind students can write their own mathematical symbols. Also included would be browsing tools that convert the MathML code into something that can be rendered in audio. Because MathML uses a structured way to represent mathematical and other symbolic systems, it should be possible in the near future to provide first-rate interactive access to equations written in MathML. See Appendix C, MathML, for more information.


Graphic information within electronic textbooks falls into three general categories:

  • Decoration: does not convey important information.
  • Information: is an integral part of the content, including text presented graphically.
  • Activation: is the trigger point for responses from the user, such as a button that causes the next page to be displayed.

The challenges in making electronic textbook graphics accessible are:

  • Differentiating between important and decorative information.
  • Indicating the presence of information presented graphically.
  • Where appropriate, providing descriptions of the graphic images.
  • Where appropriate, providing an alternative presentation, via description, tactile, or other means, for any important information that is presented graphically.
  • Text descriptions of graphical information may be either presented in parallel with the graphics for all users to see, or hidden in such a manner that it may be retrieved upon request. Increasingly, accessibility researchers are finding that when information is hidden, many users who are not blind request these text descriptions. This feature adds to the comprehension of the graphical information by individuals with perfect vision.

There is great value in the redundant presentation (i.e., the repetitive display of the information in multiple formats, such as audio, closed captioning, descriptive video, braille and enlarged type) of information. For individuals who are blind or who have visual impairments as well as for those with cognitive limitations, it is often desirable to have supplemental methods or materials available in addition to any verbal descriptions. This additional information helps in the presentation and interpretation of graphical information. Tactile models, raised line drawings, braille and audio tracks help provide orientation and information that enhance comprehension of graphical images. When a screen magnifier is used to enlarge an image, it may become grainy and unreadable. It would be desirable to supplement informational graphics with student selectable full screen versions of the graphics.

Navigational Systems

In order to move about effectively within an electronic textbook, students must be able to independently and efficiently operate and navigate the textbook. Electronic textbooks, whether created from existing texts, or crafted as new works specifically for PC or web usage, can incorporate advanced navigational capabilities that benefit all readers.

Understanding that textbooks often have varying structures (e.g., an annotated edition of a novel compared to a science textbook), it is important to provide navigational mechanisms that offer consistency in the user interface while adapting to the specific style of the given book. Students should not have to learn unique navigational commands for each book used.

Multimedia presentations, such as audio, videos and animations, also must be navigable in more than just the time dimension. To be able to search for a word or scene in a video is a major benefit for all students. This concept, already applied to talking books like Daisy, is also part of the upcoming releases of the MPEG format.

The key to an accessible navigation system is twofold:

  • The textbook must be authored through the use of standard mark-up languages such as HTML or XML so that structural elements are incorporated and identifiable.
  • The presentation system for the textbook, whether it is a web browser, specialized "book presentation" software, or a "book reader" hardware device, must be able to directly present this structure to the student, provide basic controls for navigating the structure, and indicate to the student their progress and position in the book. That is, the presentation system must answer the following questions:
    • Where am I?
    • Where have I been?
    • Where can I go?

Electronic textbooks convey the structure of the content by using several methods. These include the use of simple outlines, expanding outlines, tab folders, and image maps. Electronic textbooks also use a variety of methods to help users navigate the contents. These include the use of menus, sub-menus, buttons, tab folders, outlines, scroll bars, icons, graphics, hyperlinks, and search functions.

With hypertext documents that incorporate the concept of non-linear navigation, being able to see the "big picture" is critical. Visual metaphors for structure are useful for sighted students, but they are of no value to the visually impaired. It is important for the student who is blind or visually impaired to understand what is contained within the textbook, how the textbook is organized, and what navigation options are available. Non-visual navigation systems must depend upon the structural elements of the book to create a verbal mapping (e.g., "You are at Lesson 2 of Chapter 5. There are six lessons in this chapter. There are 10 chapters in this book"). With the availability of the structural information, any kind of verbal rendering is possible using braille or speech.

For the student who is unable to use a mouse, the navigation structure must be operable through standard mouse and keyboard controls to ensure compatibility with necessary assistive technology. Though visually oriented students may utilize the mouse to select buttons, menus, or clickable areas on a graphic, it is essential that all possible selections on any given screen have an efficient keyboard selection mechanism. Further, it should be possible to obtain a verbal summary of the number and type of selections possible, whether the selection is explicitly displayed as a button or menu choice, or implied through a clickable image. This can be done directly by the book presentation software, or through an assistive software aid that can programmatically access this information.

It will be possible to adapt a variety of alternative input mechanisms to any electronic textbook. Interfaces like W3C's DOM (Document Object Model) or an Accessibility Application Programming Interface (API) like Microsoft Active Accessibility or Sun's Java Accessibility may be used for this purpose.

The key to efficient and accessible navigation controls includes:

  • Ensuring that all navigation and control can be accomplished without a pointing device (e.g., through the keyboard).
  • Providing a visual as well as auditory means of determining the number and types of controls available.
  • Providing a capability for collapsing a document down to its major titles or components along with some indication of the length of the material beneath each title or in each component.
  • Providing a capability for presenting information that is distributed around the screen in a linear fashion whenever possible.

Again, by using the structured version of a book, it is possible to go beyond just the simple "collapsing" of a table of contents. For example, a student could activate a control that says, "Show me (read to me) only the 'chapter summaries' for the History Book." It is possible to create any view a student will find useful. Another possibility is that a teacher could create custom views of a book, "collapsing sections" that are not needed at any given time. Rather than using a specific textbook for each mathematics track, use of the same textbook, with different "filters" applied to either show or hide more advanced concepts may be better. Then, educational need, rather than fixed text format drive navigation, structure, and content of the textbook.


There is nothing inherently inaccessible about hyperlinks. The three major problems faced are:

  • identifying when something is a link,
  • understanding the context when one gets to the other end of the hyperjump,
  • having an idea of where the hyperlink goes before following it (particularly a problem for students with visual disabilities if the hyperlink is an image without associated text).

Hyperlinks are generally indicated through text formatting (e.g., the text is a different color or the text is underlined or italicized). If all of the formatting information is available to the user, the existence and location of hyperlinks is generally available as well. A descriptive hyperlink text phrase will help a student determine where the link is going and if they would like to follow it or not. For graphical hyperlinks, associate a text phrase with the image. When an individual has executed a hyperlink jump, some type of a verbal announcement that a jump has taken place is useful as a cue to the individual that the "world around their soda straw view" has changed, so that they look around and reorient themselves to the place to which they have jumped.

Expand and Collapse Features

In some cases, expand and collapse features may already be accessible. Problems arise, however, depending on how they are implemented in a given system. All expand and collapse features should be executable from the keyboard with speech or electronic text. All non-text visual cues that are provided in conjunction with the expand and collapse features should be available via built-in accessibility or revealed to the screen reader.

A subset of the expand and collapse feature would be a zoom feature. Such a feature allows individuals who are sighted to get a bird's-eye view of the general layout of the document or landscape. They can then zoom in for detail. The equivalent for those who cannot see would be the ability to provide an image that they could feel tactually. In addition, auditory cues could be provided to indicate white space, text and numbers. This would allow them to get a sense for the global layout of the page in the same way as a sighted individual.

Search Features

In addition to the ability to search for words or phrases, it is also very useful to search for character formatting or for structural items in the document. For example, the ability to search for the next title is very helpful for stepping through a document. If structure information is not available, the ability to search for the next bold or underlined text can be useful.


As with graphics, audio information in an electronic textbook can convey important information or it can be purely supplementary or decorative. For students who are deaf or have hearing impairments any information that is presented auditorially would need to be available in amplified form and as captions. For students who have both visual and hearing impairments, amplification may be helpful, but captions should also be provided in electronic form compatible with assistive technology so that they can be presented via braille. The pace at which the auditory information is presented should be controllable to allow for different levels of comprehension. For example, it should be possible to speed up, slow down, stop, pause, or replay speech and captions. The techniques needed to provide captions for audio are the same as those described in the section on fixed sequence animations and movies.

Fixed Sequence Animation and Movies

Electronic textbooks may contain full-motion video in color or black and white, with or without sound. The audio portion of the movies would be accessible to students who have low vision or blindness; however these students may have limited or no information regarding the visual information which is displayed on the screen. Students who are deaf or have hearing impairments, on the other hand, will benefit from the visuals but may not understand any of the sound. In order to make animation and movies accessible, the electronic textbook should provide:

  • Audio descriptions of the visual contents, which can be turned on and off as needed.
  • Captions of the auditory contents, which can be turned on and off as needed.
  • The ability to back up and replay some or all of the information, to pause and restart from the same place, and to slow down the rate of presentation if, for example, a student needs more time to read the captions.
  • An electronic text version of the audio captions and the audio description text for use by students who are both visually impaired and hearing impaired.

These features can be provided in a number of ways. The same multimedia tools that are used to create the original presentation could be used to add additional audio description and captions to provide these features, and the ability to turn this information on and off could be built as a part of the interface of the product. However, three popular multimedia players now provide the ability to handle audio description and captions within the media format. These formats are:

  • QuickTime 3.0 and later.
  • Microsoft SAMI (Synchronized Accessible Media Interchange) included in Microsoft Media Player version 5.2 or later.
  • SMIL (Synchronized Media Integration Language), a format adopted by the World Wide Web Consortium. One SMIL player is the G2 player from RealNetworks.

For some electronic textbooks, it may be helpful to include supplemental materials such as tactile models, raised line drawings, braille or audio materials which can provide orientation and information which would assist students who are blind or visually impaired to understand the graphic information or auditory descriptions.

Information that Changes

Information may change for two reasons: (1) In response to an interaction with the student (e.g., the student adds a new substance to a chemistry experiment); (2) The information is "live" and is continually updated (e.g., a weather map is updated to show current conditions).

  • Interactive Elements. Use of interactive materials is one of the more challenging issues, but one where recent work brings interesting solutions. Often, simulations allow the user to manipulate the components (rely on eye-hand coordination) on one part of the screen and observe the results of that action on another part of the screen. An example of this is the model four-stroke engine described earlier in this document. In that example, the user could use a touchscreen or a mouse to grab the flywheel and turn it left and right in order to see how the pistons operate. As mentioned earlier, two approaches can be taken to make interactive programs accessible: direct accessibility or compatibility with assistive technologies. For interactive portions of the electronic textbook, offering two types of support provides direct accessibility:
    1. Allow all of the manipulations on the screen to be accomplished independently from the mouse (i.e., from the keyboard). This would also be useful for individuals with physical disabilities, who could use an alternative input device such as a single switch or speech recognition to manipulate the components. Other students, with and without disabilities, may also benefit from using keyboard access or speech recognition.
    2. Provide meaningful auditory cueing, or feedback, that communicates the status or change in status of the various components. Such auditory enhancement of the visual picture is crucial for blind students and is usually beneficial for students with cognitive impairments as well as students without disabilities.

Combining keyboard or alternative input with audio feedback creates an interface that students can use regardless of whether they can see the screen or they can use a mouse. If the additional audio is found to be a distraction to students who do not need it, the program should offer an option to turn it off.

Compatibility with assistive technologies is a second approach. It is crucial for use by students with some disabilities, such as those who are deaf-blind and use a braille display rather than audio information. For this reason, even directly accessible simulations should be access technology-compatible. However, using educational programs in conjunction with assistive technologies is less appropriate for some students, including younger students.

Technologies are now available that enable developers to design software which is compatible with assistive technologies, providing an important advance in the ability to create accessible software. These technologies are known as Applications Programming Interfaces (APIs). A possible compatibility solution for software built for the Windows platform is Microsoft's Active Accessibility (MSAA), an API for exposing elements of the screen and their state, including exposing the focus of the screen. Using MSAA, software developers can use entirely graphical custom interfaces while still making each element known to a screen reader. This makes it possible to provide access to every control and output of a simulation.

The growing popularity of Java as a programming language for the Internet has led to the development of the Java Accessibility API. With some similarities to MSAA, Java Accessibility allows software developers to expose the location, name, and state of each control while still using the graphical look-and-feel of their choice. For programs being developed in Java, this is an important tool.

Caution must be used when designing modifications of interactive animation and simulations to ensure that the same quality of information is provided to the student who is blind as is provided to other students. In the example of the piston engine, the purpose of the program was to teach a child a specific concept. Even with the adaptations, the student who is blind would not have sufficient access to the information on the screen to learn that concept. Additional hands-on instruction with tactile adaptations, physical models, or other materials necessary for the student to grasp the concept would be provided by a teacher trained in the education of students with visual impairments. Wherever possible, content creators should suggest models that may be constructed from ordinary items. This will help all teachers provide the alternative learning tools that may benefit all students.

Other programs could be modified successfully using only changes to the software. For example, a program might provide an animated story which periodically stops until the child responds to specific directions or answers questions by using the mouse or touchscreen. If there were a verbal (sound or tactual) narration of the story, and the student responses could be provided through the keyboard, then the child who is blind would have adequate accessibility to the content and could achieve the same results as other students.

Simulations often provide students with opportunities they might not have in everyday life - particularly students with disabilities. Handling beakers, flasks, burners, and other equipment in the chemistry laboratory is often not safe for students with visual or cognitive impairments and often not possible for students with physical disabilities. Manipulating the equipment via computer simulations allows students with vision to witness chemical reactions (e.g., color changes, heating, and explosions). Presenting the results of the manipulations through appropriate sound and descriptive narrative allows the student who is blind or has low vision to participate and have information similar to that, which is available in the chemistry lab. Allowing students to manipulate apparatuses via the keyboard includes students with physical disabilities and blindness in the experimentation process.

For some interactive materials, as with fixed sequence materials, it may be helpful to include supplemental materials such as tactile models or raised line drawings.

  • "Live" Information. "Live" information may either be generated by a person (discussions in a chat room, see section below Collaborative Environments) or a machine (photographs of an African water hole taken at 30 second intervals). The strategies discussed in the previous section (interaction and simulation) do not always apply to live information since the textbook does not include the "live" information to be presented. For example, the textbook publisher cannot provide the description of the activity at the water hole in advance of the activity. In the future, software may exist that can analyze the photograph and create these descriptions, but until then other strategies must be used. Some of these are as follows:
    1. For information that is inherently textual (such as discussions in a chat room), ensure that the text is drawn with standard text drawing routines (see the first topic in this section, "Text").
    2. For digital information (such as weather information - wind direction, temperature, wind speed, etc.), if it is displayed graphically (e.g., a thermometer) ensure that the digital information is available.
    3. For modality specific presentations of information, such as a weather map showing current cloud cover (which is purely graphical), ensure that a description of the basic content of the information is provided. For example, attach the phrase, "Current cloud cover of Dallas" to the weather map.
    4. For information that is cyclical, provide descriptions of the major components to be covered by the material. For example, a group of researchers and educators watch chicken embryos develop over the course of a semester by using live MRI images of eggs. The class discusses what they see at each major stage in the development cycle. Since the chicks develop the same features roughly at the same time each semester, the descriptions won't change much each time the experiment is run. The problem occurs when an abnormality occurs and the descriptions do not fit with the current conditions. In this case, it could become a classroom exercise to generate the descriptions to add to the database for future experiments that might go the same way.
    Live information websites not controlled by the electronic textbook publisher should be checked for accessibility before selection for inclusion as a resource in an electronic textbook. Providing these sites with the World Wide Web Consortium's Web Accessibility Guidelines may increase the accessibility of the sites in the future.

Collaborative Environments

Collaborative environments allow students with disabilities to interact in communities they might not otherwise have the chance to interact in. They also provide able-bodied students the ability to interact with students with disabilities. An electronic textbook could be designed giving students the ability to collaborate, through the use of collaborative tools (e.g., chat, e-mail, discussion forum, or videoconference) with study peers or a study team to write reports, share research data, or share a "white board" or area of the screen where they can draw, write, calculate, or otherwise work together on the same "piece of paper." Electronic textbooks can provide direct accessibility to collaborative interaction (which is sometimes "live") by choosing accessible tools for videoconferencing, chat, e-mail, and other collaboration tools. If the collaborative tools are developed specifically for the electronic textbook then these tools should be directly accessible or compatible with assistive technology.

For example:

  • Where white boards or shared areas of the screen are used for drawing, writing, or otherwise working together, it is important that the white board area be implemented in such a way that it has either built-in voicing or works in conjunction with a screen reader for textual information. It should also be possible to print out or save the contents of the white board so that it may be converted into a raised line drawing using special adaptive equipment.
  • If the collaboration tool allows for voice communication, it should also provide a text communication alternative (e.g., text chat or real-time captioning) for students who are hearing impaired or deaf. Or the school should provide an interpreter.
  • Controls for the videoconference should be completely operable without vision or without a mouse. Providing keyboard access to all of the videoconferencing controls is the easiest and most reliable way to achieve this.
  • Collaboration tools that provide live text communication (chat) should be self-voicing or be compatible with screen reading technology.
  • In all cases, the collaborative tool should permit the keeping and saving a session log of all interaction. The log should be available to students in an accessible form for replay or printing.

Live collaboration and videoconferencing is inherently no less accessible than face-to-face communication. It is up to the individuals who are communicating to make sure that information is accessible to each other. Basic information on how to communicate in an accessible manner should be provided to a live (human) resource before inclusion in an electronic textbook.

Virtual Reality: Three Dimensional or Immersive Environments

For students who have little voluntary movement, immersive environments can provide valuable alternatives to the experiential learning opportunities they have missed or only passively observed. As long as the environment can be efficiently controlled using keyboard equivalents, these students can control the experience using alternative keyboards or keyboard emulators. A number of strategies can be employed to make navigation and object manipulation easier and more efficient for all students. These include:

  • allowing the educator or student to constrain the planes of movement,
  • providing preset, easily selected, routes to objects or locations,
  • providing preset points of view that can be selected using a minimum number of keystrokes.

For students who cannot use the visual modality, immersive environments in their present state do not add to the learning experience. Providing text or audio labels, descriptions and meta data can provide some access to the information in the three dimensional scene, but the experience remains more frustrating than rewarding. Wayfinding in a virtual world, with few constraints on travel, can be a daunting task even for a student with full vision. This situation may change dramatically with the development and broader availability of haptic interfaces and three-dimensional sound displays. "Haptics" is a term that encompasses both the sensing and action involved in touching and manipulating.

For many students haptics is the preferred mode of exploration. Unlike the visual and auditory modality, by its very nature it is interactive. We manipulate the objects we are sensing in a continuous action-feedback-reaction loop. Thus many people do not feel they have really "seen" an object unless they have handled it and explored it with their haptic sense. With the addition of haptic rendering and haptic display/control devices, three dimensional, immersive curriculums can bring a multitude of objects and environments to the classroom for exploration by all students, including students who are blind. Three dimensional, immersive environments will become more accessible and usable as additional display and control modalities become feasible and widely available. Wherever possible electronic textbooks that include these tools should support multiple display and control modalities and provide information in redundant formats. Virtual reality environments can be divided into two general categories:

  • The individual is experiencing a visual immersion. One example is a virtual reality environment that is used to allow an individual to walk through an art gallery.
  • The use of virtual reality as a metaphor for something that is not inherently visual. For example, there are a number of virtual reality tools being used to navigate knowledge bases.

In the first case, the virtual reality is simply another way of presenting visual information. Being inherently visual, the student who is blind did not previously have access to the information. However, by making the presentation electronic, it is possible that additional access may be provided through the use of techniques and technologies for image enhancement and edge identification. These could be used in conjunction with tactile printers (e.g., braille printers) and raised-line drawings. In the second case, it is important that visualization tools created to navigate the information space preserve a nonvisual (e.g., verbal/textual) interface for those individuals who cannot use the visualization interface.

Media-specific Strategies

  • Videotape. The most common form of classroom videotape is 1/2" VHS. For classrooms that include students who are blind or visually impaired, videotapes with verbal descriptions of the visual information are needed. Since there currently is no technical way to hide or embed these verbal descriptions in the videotape and turn them on when needed, as is possible with captions, the verbal descriptions should be a part of the standard audio track on the tape. These verbal descriptions take the form of narration which is added between the normal audio information on the videotape. The added narration describes what is occurring visually on the screen. One approach for providing verbal descriptions on videotape would be to have two versions of the tape, one with the verbal descriptions and one without the verbal descriptions. A second strategy would be to record descriptive video and sound information on one track and sound information only on the second track. Users could then select either the left or right channel to get the material with or without the verbal descriptions. Individuals would be able to turn the audio descriptions on or off as desired. Neither of these techniques is optimal, but both do work within the constraints of current videotape technology. For classrooms that include students who are deaf or hearing impaired, videotapes with closed captions of the auditory information are needed.
  • Videodisc. When produced in a non-interactive manner, videodiscs can be treated much the same as videotapes, with one important difference. Videodiscs have the capacity to include an additional sound track for descriptions. As a result, both stereo channels can be used for the regular audio, with the verbal descriptions on yet another channel which can be turned on and off as needed by the students. For disks that are produced with a higher degree of interactivity, not only do the moving images on the disk need to be described, but the visuals and text on the computer screen need description and translation into digitized speech, braille display, or enlarged type. Although this may sound very difficult, when taken one element at a time, access to many types of interactive videodiscs is possible. The guidance for such access can be taken from the means for making standard linear video accessible and for making multimedia software accessible. In general, this type of accessibility also has benefits for individuals without visual impairments.
  • Multimedia Software. The same principles that apply to accessible electronic textbooks apply to multimedia software. By its very nature, multimedia software allows even more flexibility than videodiscs in terms of the opportunity for multiple channels of video and audio information, all of which can be turned on and off at the user's discretion. In most cases, however, accessibility to multimedia software must be built in. The capability of assistive technology such as screen readers to track and interpret what is happening in a multimedia environment is very limited due to inaccessible design. Both digitized audio, digitally recorded human voice, or synthesized audio computer-generated voices, can be used to provide access to and describe essential visual elements to students who are blind or visually impaired. Captions for all audio information is a necessity for students with hearing impairments. As discussed previously, the ability to access and use the system without eye-hand coordination is very important. Keyboard control of the program is an excellent strategy here.

Costs Associated with the Development of Accessible Instructional Materials

The Access to Multimedia Technology by People with Sensory Disabilities (1998) report from the National Council on Disability (NCD) estimated that the cost of making a CD-ROM accessible is 2.0-2.5 percent of the total cost of development and production. An unknown is the cost, in terms of time and money, of textbook publishers and their developers learning how to make their products accessible. The same NCD report stated that once developers learn about accessibility issues, they are interested in making their products more accessible. In the past there was limited knowledge and information available on developing accessible products. This is no longer true. Accessibility of products and information has become a worldwide issue. There is no longer a shortage of information, tools, or professionals with expertise in the development of accessible information. Examples of specific media accessibility costs are as follows:

  • To produce an audio description of 60 minutes of video material would cost $3,300.
  • To produce captioning of 60 minutes of audio or video material would cost $1,000-$1,500.
  • To produce a 60-minute recording of printed material would cost $350 - $650 (based on a recording rate of 15-20 print pages/hour).


Feasibility and Cost-Effectiveness of Developing Accessible Electronic Textbooks for Students with Disabilities

Texas school districts use technology for students with disabilities, ESL students, and at-risk students.

Districts use a wide range of assistive technology for students with disabilities. Some districts have assistive technology teams that assess technology needs, modify and install assistive hardware and software, and train teachers, students, and parents. Special education teachers in some districts enhance their knowledge about adaptive technologies and the latest research by accessing the Internet and participating in chat rooms with peers.

Electronic textbooks and ancillaries are becoming available in a multiplicity of media including interactive media. However, they are also becoming less accessible and usable by students with disabilities. As textbooks move away from a paper delivery medium they become more difficult to produce in braille, large print, and audiotape. Texas is again leading the way in laying the groundwork for ensuring that new electronic textbooks will be usable by all students, including those with disabilities. The Texas Education Agency is investigating the use of networks in schools and pursuing pilot projects to develop accessible textbooks. It is entirely feasible that within the next six years, all new electronic textbooks in Texas classrooms will be accessible and usable by all students.

Districts use similar strategies with ESL students and teachers. Districts use technology also with at-risk populations.


  • The infusion of schools with technology has had an impact on the Special education area. Schools provide a wide range of assistive technology to students with disabilities, offer special content and online modified tests, and train teachers, students and parents in the use of technology.
  • The accessibility of an electronic textbook depends upon the design of the electronic textbook. The Texas Education Agency report to the 74th Legislature entitled Accessibility of Information in Electronic Textbooks for Students who are Blind or Visually Impaired detailed the requirements for constructing an accessible electronic textbook. At that time, there was limited knowledge and information about developing accessible electronic textbooks. This is no longer true. Accessibility of products and information has become a worldwide issue. There is no shortage of information, tools, techniques, or professionals with expertise in development of information necessary to produce most electronic textbooks in an accessible format.
  • Ensuring that the electronic textbooks likely to be adopted in the future are designed and developed to be accessible by students in the most logical and cost-effective manner requires collaboration among textbook publishers, media accessibility developers, software and hardware developers, teachers of students with disabilities, consumer advocates, Internet and online service providers, and state government.
  • Providing accessible electronic textbooks to schools benefits all students including students with disabilities. For example, on-screen information that is spoken not only helps visually impaired, reading disabled, dyslexic, and other students with disabilities, but also students who are bilingual, have limited English proficiency, or those who learn better by receiving multi-modal (auditory and visual) input. Keyboard control and navigation, in addition to mouse control and navigation of instructional materials, helps students who cannot use a mouse because of a visual disability, a motoric disability, poor eye-hand coordination, or temporary injury. Video materials that are closed-captioned or that have descriptive audio tracks also provide multi-sensory input, enhancing comprehension.
  • When accessibility is designed into the textbook itself, learning activities can be customized, not just for students with disabilities, but for all students. Thus, the learning benefits accrue not just to those who most urgently need these accommodations but to mainstream learners as well.


  1. Authorize and fund the establishment of an advisory committee of instructional designers, textbook publishers, accessibility experts, disability specific educators, and regular educators to develop guidelines and recommendations for designing accessible, meaningful, and understandable interactive electronic instructional materials including simulations.
  2. Fund a thorough study of the financial implications of developing accessible electronic textbooks.
  3. Authorize and fund the establishment of two demonstration projects to develop two interactive electronic textbooks. These should be:
  4. A directly accessible CD-ROM-based textbook that students with disabilities could use without assistive devices.
    An interactive accessible Internet-based or Intranet-based textbook that students with disabilities could use without assistive devices.
  5. An advisory committee should monitor the progress of the demonstration projects and provide feedback to the Texas Education Agency.
  6. Require that beginning with year 2003 (Proclamation 2001) all CD-ROM textbooks or materials adopted by the State Board of Education comply with the basic accessibility requirements on pages 88-89 of this report approved by the Texas Education Agency.
  7. Require that beginning with year 2003 (Proclamation 2001) all Internet-based or Intranet-based textbooks adopted by the State Board of Education comply with the accessibility guidelines of the World Wide Web Consortium.
  8. Require that all materials purchased by Texas public schools for preparing students to take standardized and college entrance examinations be accessible to students with disabilities.



  • United Nations, Division for Social Policy and Development (1998) Accessibility on the Internet
  • This special report intends to provide an overview of Internet accessibility and to serve as a select resource to some of the initiatives launched by individuals, organizations and companies.
  • National Braille Association. (1979) Tape Recording Manual National Braille Association, Inc. 654A Goodwill Avenue Midland Park, NJ 07432
  • Edward Roll Tuft (1990) "Envisioning Information." Graphics Press, P.O.Box 430, Cheshire, CT 0650% "The book, with more than 400 illustrations, provides practical advice about how to explain complex material by visual means, and uses examples to illustrate the fundamental principles of information display."

Captioning resources:

Captioning software:

  • A comprehensive list of software for doing your own captioning is at
  • A new tool for adding captions and descriptions to digital media, including SAMI, SMIL, and QuickTime, is being developed by WGBH and the Trace Center and will be available soon. For more information contact:
  • The CPB/WGBH National Center for Accessible Media
    125 Western Avenue
    Boston, MA 02134
    (617) 492-9258 (V/TTY)
    (617) 782-2155 (Fax)

Description resources:

  • Descriptive Video Service, WGBH
    125 Western Avenue
    Boston, MA 02134
    (617) 492-2777 extension 3490
    Ray Joyce, Director
  • The Metropolitan Washington Ear, Inc.
    35 University Blvd. East
    Silver Spring, MD 20901
    (301) 681-6636 (301)
    681-5227 (fax)
    Margaret Pfanstiehl, President
  • Narrative Television Network
    5840 South Memorial Drive, Suite 312
    Tulsa, OK 74145-9082
    (918) 627-1000
    (918) 627-50%1 (fax)
    Jim Stovall, President

Software and Operating System:

World Wide Web Accessibility information:

  • World Wide Web Consortium. "Web Accessibility Initiative - Accessibility Resources" Working drafts of the various accessibility working group guidelines, specifications and other resources.
  • World Wide Web Consortium. "Synchronized Multimedia Integration Language W3C working draft." The specification for SMIL, a protocol for integrating many types of media on the Web or on CD-ROM. Can be used to add captions and audio description.
  • Just SMIL. "Just SMIL." General information on the SMIL protocol, including tutorials, examples, and news.
  • Closed captioning is supported by the Windows Media Player version 5.2 or later. For more information, see the web sites available at
  • NISO. Digital Talking Book Standard
    Information about a national standard for a digital talking book (DTB) for blind and physically-handicapped readers. A DTB is envisioned to be, in its fullest implementation, a group of digitally-encoded files containing an audio portion recorded in human speech; the full text of the work in electronic form, marked with the tags of a descriptive markup language; and a linking file that synchronizes the text and audio portions. As this document illustrates, such a structure will allow the DTB user a broad range of capabilities not possible in current talking books.

Resource on MathML:

  • Further information on MathML is available from the W3C's Web site This page includes links to the MathML specifications and to software companies who create math tools and plan to incorporate MathML support.

Accessibility Information Concerning Math and Science:

CD-ROMs for Math and Science

by Madeleine Rothberg and Tom Wlodkowski, CPB/WGBH National Center for Accessible Media This is an instructive article that looks at various pieces of math and science software to evaluate their usefulness for people with vision impairments. The article also makes suggestions on how to make the programs more accessible for individuals with vision impairments.

Computer-Based Concept Mapping: Promoting Meaningful Learning in Science for Students With Disabilities

by Lynne Anderson-Inman, Ph.D. & Leslie A. Ditson, Ph.D., University of Oregon & Mary T. Ditson, M.C.A.T. This paper describes the process and benefits of concept mapping and its use for helping students with learning disabilities study science. It includes four graphics that illustrate the concept maps. The graphics have full text descriptions.

Instructional Design that Accommodates Special Learning Needs in Science

by Bonnie Grossen & Mack D. Burke, University of Oregon, This paper addresses six important teaching strategies for "diverse learners," students who have backgrounds, foundations, or abilities that differ from most students. While it encompasses a wide variety of students, an important segment of this population is students with disabilities. The ideas presented here have definite value for teachers, service providers and others who work with students with disabilities. There are also some valuable program evaluations at the end of the article.

Hitting the Books: Accessible Textbooks for K-12 Math and Science Education

by Stephen L. Noble, Recording for the Blind and Dyslexic, This article is a comprehensive overview of the problems that K-12 students encounter using textbooks and some accessible text formats that are currently available. In particular, the article looks at the special problems posed by math and science texts for K-12 students with disabilities.

Audio-Assisted Reading: Access for Students with Print Disabilities

by Carol Evans, Graduate Student in School Psychology, University of Utah, This short article focuses on another dimension to using books on tapes - using recorded books along with texts. This is particularly beneficial for students with learning disabilities.

Math and Science from a Home-School Perspective

by Pat Guthrie, Home School Teacher, This article is different from most that are published in the ITD. It is a very personal account of a woman who has chosen to home-school her son who has several disabilities due to a brain injury. She has worked with the school system to put together a program that combines her home-schooling with a couple of classes at the high school. For the most part this woman uses low-tech strategies, but she has included work on the computer in her son's curriculum. This is a very human look at many of the issues that we often view only from the practical, institutional or technological perspective.

Transitions for Success: Helping K-12 Students Move Through the Public School System

by Carmela Cunningham, EASI, This article looks at some of the challenges and problems that students with disabilities encounter when they move through the educational process. It gives some practical tips for service providers and focuses on the idea that one plan or strategy will not work well for all students.


Applications Program: Any computer program that enables the user to accomplish some tasks, but not a task relevant only to the computer's operation. For instance, a word processing program would be an applications program because it enables the user to create, edit and print text.

ASCII (American Standard Code for Information Interchange): A standardized system which assigns letters, numbers, and various other characters each their own code. This allows information to be transferred successfully from one computer to another via various interfaces.

Assistive Technology Device: Any item, piece of equipment, or product system, whether acquired commercially off the shelf, modified or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities.

Audio Video Interleave (AVI): The audio and video file format for Microsoft Windows Media player.

Bit Map: A set of numerical values specifying the colors of pixels on an output device.

Braille: A system of writing and reading used by individuals who are blind. This system is based on characters made up of raised dots.

Browser: Also called a Web Browser. A program that enables you to explore the World Wide Web.

CD-ROM: (Compact Disk--Read Only Memory): A form of storage like a floppy disk except that it is usually permanent (read only) and has a high storage capacity (typically 650 megabytes). A CD-ROM disk looks like an ordinary stereo CD, however, a CD-ROM is used to store computer data rather than music.

Chat: Real-time communication between two or more computer users on the Web. Once a chat has been initiated, either user can enter text by typing on the keyboard and the entered text will appear on the another user's computer screen.

Device: Any identifiable subsystem of a computer. Drives, video circuitry, printers, the keyboard, the mouse, and ports are devices.

Discussion Forum: An online discussion group. Forums do not provide real-time communication. A variety of web sites provide forums, in which participants with common interests can discuss topics with open messages.

Digital: Operating in discrete units or steps, not continuous. Since microcomputers operate using discrete voltages and timing pulses, they are said to be digital. Usually contrasted with analog.

DOM: Short for Document Object Model, the W3C specification for how objects in a Web page (text, images, headers, links, etc.) are represented.

DVD (Digital Videodisc): A hardware technology designed to replace audio and information CDs, laserdiscs, and even videotapes. Each DVD can hold the equivalent of seven times a regular CD (more than 120 minutes of video).

Dynamic Braille Display: A computerized electro-mechanical device which displays braille using pins or other means that permit the braille to be changed as each line is read. An electronic code sent to the system raises and lowers the pins to form braille characters which the user can sense by placing the fingers on top of the display. When the display is full, the first cell recomposes itself and the display fills up again.

Electronic Mail (E-Mail): A system whereby a computer user can exchange messages with other computer users (or groups of users) via a communications network. Electronic mail is one of the most popular features of the Internet.

Electronic Text: Textual information stored in a digital form that can be presented on a computer screen. Normally this can also be presented in braille or as enlarged characters on a computer screen.

GUI (Graphical User Interface): A way for humans to communicate with a computer that typically uses graphics mode instead of character mode. Usually involves the use of a mouse.

Hardware: Any component of an electronic system which is tangible (e.g., a computer, a monitor, a disk drive, or a printer). This category contrasts with software, which describes those components which consist only of electronic signals (e.g., programs, text files, and other quantities of information that can be stored on a disk or in a computer's memory).

Homepage: A collection of graphical and textual data organized in such a way as to facilitate easy access to all of the information it contains. Hypertext may be thought of as a precursor to multimedia, or simply as an extension of it.

Hypertext Markup Language (HTML): The language used to create pages for the Web. Computer commands enable users to specify different fonts, graphics, hypertext links and more.

Graphics Interchange Format (GIF): A bit-mapped graphics file format used by the Wide that supports color and various resolutions. It also includes data compression for fast delivery of images.

Internet: The name given to a large network of computers that are connected by high-speed information or data lines. The Internet also refers to the different services you can use on the Internet. Some of these activities include electronic mail and the Web.

Intranet: An organizational network only accessible by members of the organization.

Java: Java is a computer programming language. It has gained a lot of popularity because of its cross-computer support. That is, Java programs written for one computer operating system will also work on other computer operating systems, which saves the programmer from having to re-write the program to get it to work on several types of computers.

Joint Photographic Experts Group (JPEG): A compression technique for color images. It can reduce files sizes to about 5% of their normal size with some loss of detail. Used for sending images quickly over the Internet.

Math Markup Language (MathML): A new specification developed by the W3C. It is a language similar to HTML, to be used to send mathematical and other scientific equations and information over the Web. It will facilitate the production of printed materials, as well as making math and other scientific content accessible to people with disabilities.

Moving Picture Experts Group (MPEG): The collection of digital video compression standards and file formats developed by the MPEG group. Used to send video quickly over the Internet.

Modem: Short for modulator-demodulator. A device that enables a computer to communicate with other computers over telephone lines.

Multimedia: Combining static media (such as text and pictures) with dynamic media (such as sound, video, and animation) on the same system.

Object-Oriented: Generally used to describe an illustration or font file as being created by mathematical equations.

OnLine Service: A commercial service that provides capabilities such as e-mail, discussion forums, technical support, software libraries, news, weather reports, stock prices, plane reservations or electronic shopping malls. To access one, you need a modem.

Operating System: The program that allows the various parts of a computer system to "talk" to each other. The operating system is usually the first thing "loaded" after a computer is turned on, as most other programs require it in order to run.

Optical Character Reader (OCR): A device which can optically analyze a printed text, recognize the letters or other characters, and store this information as a computer text file. OCRs are usually limited to recognizing the styles and sizes of type for which they are programmed.

Platform: Specific computer hardware, as in the phrase "platform-independent."

PostScript: A computer language for describing a printed page commonly used to drive office printers. Many fonts, graphics programs, screen drivers, and printer drivers use PostScript.

QuickTime (QTM): A method of storing audio and motion picture video information on an Apple Macintosh computer. It is used to record and play back multimedia information and store the data on magnetic or optical media. QuickTime is also a collection of tools which allows movies to be modified (edit, cut, copy, and paste) just as a word processor is capable of modifying ordinary text.

Synchronized Accessible Media Interchange (SAMI): A markup language developed by Microsoft to simplify captioning of Web-based media files.

Screen Reader: A program which speaks the contents of the computer's screen via a speech synthesizer. Such a program is usually also equipped with a system that allows the user to "navigate," or find his or her way around the screen, without the necessity of seeing the screen.

Search Engine: A program on a remote machine that allows keyword searches on the Internet.

Synchronized Multimedia Integration Language (SMIL): A new markup language developed by the W3C that enables Web developers to divide multimedia content into separate files and streams (audio, video, text, and images). The files can be sent to a user's computer individually over the Web. The web browser would display them together as if they were a single multimedia stream.

The part of a computer system which is not tangible; that is, the programs of information that are processed by a computer or stored in memory. Commercially available software is usually sold in the form of a program or programs stored on a disk.

Standard Generalized Markup Language (SGML): A system for describing structural divisions in text (i.e., title page, chapter, scene, and stanza), typographical elements (changes in typeface, and special characters), and other textual features (grammatical structure, location of illustrations, and variant forms).

Tags: Formatting codes used in the Hypertext Mark-up Language (HTML) documents. These tags indicate how the parts of a document will appear when displayed by a Web client program.

URL (Uniform Resource Locator): A code which provides the exact location of a resource on the Internet, and describes the type of resource.

User Interface: The aspects of a computer system or program which can be seen (or heard or otherwise perceived) by the human user.

Videoconference: Using computers, with cameras and microphone, and the Web to allow people in remote locations to have a live discussion in which all parties can see and hear each other.

Virtual Reality: An artificial environment created with computer hardware and software that is presented to the user so it appears and feels like a real environment. A user wears special gloves, earphones, and goggles, all of which receive their input from the computer system. In addition to providing sensory input to the user, the devices also monitor the user's actions and respond accordingly based on the computer program.

VHS: Video recording format and medium in wide use in conjunction with television technology, offering horizontal resolution of 240 lines (not considered broadcast quality).

WAV: A file format for audio files on the Windows platform.

Web Browser: A program which enables an individual to explore the Web.

Word Processor: A type of applications software that is used to enter, edit, manipulate, and format text. In order to be considered a word processing program rather than a simple text entry and editing program, a program should have fairly sophisticated capabilities.

World Wide Web (WWW) or W3: A graphics-rich hypermedia document presentation system that can be accessed over the Internet using software called a Web browser.

World Wide Web Consortium (W3C): An international consortium of companies involved with the Internet and the Web. The W3C's purpose is to develop open standards so that the Web evolves in a single accessible direction rather than being splintered among competing factions.

eXtensible Markup Language (XML): A new specification developed by the W3C. XML is a sub-set or smaller version of SGML. Specifically for Web documents, it enables designers to create their own customized tags to provide functionality not available with HTML.

Texas Education Agency

Division of Textbook Administration

Appendix A

Computer Network Study Project Advisory Committee

David Sharp, Chair
Lufkin Independent School District
Lufkin, Texas

Senator David Sibley
Waco, Texas

Representative Scott Hochberg
Houston, Texas

Senator Eliot Shapleigh
El Paso, Texas

Representative Ric Williamson
Weatherford, Texas

Warren Alexander
Deputy Superintendent of Administration
Northside Independent School District
San Antonio, Texas

Adam Gierisch
Student, McCallum High School
Austin Independent School District
Austin, Texas

Tom Anderson
Jostens Learning Corporation
Austin, Texas

Anita Givens
Senior Director
Instructional Technology
Texas Education Agency
Austin, Texas

Richard J. Callahan
Director of New Media
Logal, Inc.
Arlington, Massachusetts

Bob E. Griggs
Birdville Independent School District
Haltom City, Texas

Rebecca Collier
Belton Independent School District
Belton, Texas

Phil Hester
Vice President/General Manager
Network Computer Division
IBM Corporation
Austin, Texas

Paul Cruz
Assistant Superintendent
Laredo Independent School District
Laredo, Texas

Mimi Jigarjian
Vice President and Regional Director of
Multimedia and On-line Services
Prentice Hall, Inc.
Needham Heights, Massachusetts

Beth Fischenich
Assistant Superintendent of
Secondary Schools
Beaumont Independent School District
Beaumont, Texas

Larry Nelson
President and C.E.O.
Decision Development Corporation
San Ramon, California

Cathy Kinzer
Manager, Strategic Software Technology
Intel Corporation
Los Angeles, California

Mark Pape
Student, Bastrop High School
Bastrop Independent School District
Bastrop, Texas

Bryan LaBeff
Executive Director
Region XVIII Education Service Center
Midland, Texas

Wynde Reneke
K12 Education Market Development
Oracle Corporation
Sanford, Florida

John Lent
Vice President, New Media
Scholastic, Inc.
New York, New York

Jacob Schlumpf, Jr.
Education Team Director
Compaq Computer Corporation
Houston, Texas

Nancy Little
Project Director, EDLINK 12
Region XII Education Service Center
Waco, Texas

Jamesetta Seals
Instructional Technology Coordinator
Houston Independent School District
Houston, Texas

Rick Martinez
Director of Instructional and
Information Technology
Alamo Heights Independent School District
San Antonio, Texas

Maria Seidner
Director of Bilingual Education
Texas Education Agency
Austin, Texas

Charles Mayo
Program Administrator
Textbook Administration Division
Texas Education Agency
Austin, Texas

Landon Shultz
Austin Independent School District
Austin, Texas

Dan McCormack
Education Technology Consultant
Apple Computer, Inc.
Austin, Texas

Jennifer Stamper
Information Technology Officer
Mesquite Independent School District
Mesquite, Texas

Ron L. McMichael
Deputy Commissioner for Finance and Accountability
Texas Education Agency

Brian Taylor
Vice President, Marketing, School Division
International Thompson Publishing Co.
Cincinnati, Ohio

Randy Merriman
Vice President, New Media
Holt, Rinehart, and Winston
Austin, Texas

Nancy Vaughan
Director, Information Systems
Texas Education Agency
Austin, Texas

Martha Veale
Technology Coordinator
Fabens Independent School District
Fabens, Texas

John Westbrook
Southwest Educational Development Laboratory
Austin, Texas

Greg Witmer
Director of Multimedia
McGraw-Hill Educational Publishing Group
Worthington, Ohio

Accessibility Subcommittee

Jim Allan, Chair
Teacher, Technologist and Webmaster,
Texas School for the Blind and Visually Impaired
Austin, Texas

Andy Amberson
North East Independent School District
San Antonio, Texas

Martha Murrell
Program Administrator for
Special Education
Texas Education Agency
Austin, Texas

Wendy Chisholm
Human Factors Engineer
Trace Research and Development Center
University of Wisconsin
Madison, Wisconsin

Madeleine Rothberg
Project Director
National Center for Accessible Media
Boston, Massachusetts

Burt Gross
Lancaster Independent School District
Lancaster, Texas

Taryn Schriewer
Student, Cypress-Fairbanks Independent
School District

Mark Hakkinen
Senior Vice President
Productivity Works
Trenton, New Jersey

Christy Shepard
Teacher, Cypress-Fairbanks Independent
School District
Houston, Texas

Sharon Komorn
North Texas Taping and Radio for the Blind
Dallas, Texas

Jutta Treviranus
Adaptive Technology Resource Centre
University of Toronto
Toronto, Ontario