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Article citation: Osterhaus, S.A. (2002). Susan's math technology corner: The Accessible Graphing Calculator (AGC) from ViewPlus Software. Division on Visual Impairments Quarterly, 47(2), 55-58.


The latest math technology need for the blind is a talking graphing calculator with the sophistication of the Texas Instruments series. The use of a graphing calculator is now an integral part of advanced mathematics classrooms across the U.S., and they are a requirement in many statewide assessments.

The Accessible Graphing Calculator (AGC) is a computer software program and was developed by the esteemed Science Access Project at Oregon State University, directed by Dr. John Gardner. This group is dedicated to the development of methods for making science, math, and engineering information accessible to people with print disabilities. "Print disabilities" include low vision, blindness, and dyslexia. In April 2000, I began beta testing the AGC. By the summer of 2000, students were being introduced to the AGC as well. During the 2000/2001 school year, all of my Algebra I and ATTAM (Adaptive Tools and Technology for Accessible Math) students were taught the use of the AGC. On March 7, 2001, ViewPlus Software Inc. (exclusive distributor) announced the availability of the AGC to the general public.

As you know from previous evaluations, I am always looking for the "best buy" in any math technology. However, although my definition of best buy includes price affordability - user-friendliness, features, and reliability are equally important.


5-Point Star: $75You may download a free 30-day fully functional copy of the AGC from the web at Then, check it out for yourself to make sure that it is the right product for your needs. When purchased on-line, the cost of a single copy license is just $75. CD copies are also available at a cost of $10 each, but this is not a necessity. Substantial institutional quantity discounts are available as well. 


The AGC was developed from the ground up to be a universally usable Windows 95/98/ME/NT/2000 computer program that features a graphing calculator capable of displaying graphs both visually and audibly as a tone graph. With technology specifically designed for the blind, we often find that although it may be user-friendly for the blind student, there is an extensive learning curve for their sighted teacher. Since the AGC is truly accessible by both the blind and sighted, teachers, parents, and peers do not need to learn to use a special device in order to teach or assist these students.

In fact, the regular ed math teacher may very well wish to use the AGC with the entire class. In this day and age when math anxiety is rampant, and there is an emphasis on multiple modality input, the math teacher is always looking for any tool that will capture the attention of and increase understanding in all her students.

The AGC is a complex program and requires some practice before a student will become proficient and totally independent in its use. However, I have noticed that those of my students already technologically proficient in the use of JAWS (or other screen reader) are the quickest to learn how to navigate in the self-voiced AGC. In fact, these students are so intrigued with the AGC features; they take the initiative and beg to use their own after school time to practice. Everyone wants to have his or her own copy for home use. I promise this is really true and not just the ravings of an over-enthusiastic math teacher.

Also, it is not necessary that the student learn all of the features of the AGC at once in order to benefit from its use. I feel that various features should be slowly introduced as needed, and the AGC should never replace the student learning how to graph manually. My best students know how to use all the various tools in their toolbox.

The AGC comes with an HTML and a self-voiced user manual, getting started instructions, specific instructions regarding the use of screen readers and magnification, and help both off and on-line.

Screen shot of AGC, showing a function plot.


The AGC has a scientific keypad calculator; an expression evaluator with the ability to define or import constants and expressions; two data set pages that permit the user to compute expressions, import and edit data tables, and compute a number of standard statistical properties; and the ability to plot either data set, their sum or difference, or their first derivative. However, you cannot plot two or more expressions on the same graph (no parent functions), nor can you do computations with matrices. There are several display options for tone-graph audio plots, and it is self-voicing for usability by people who are blind or dyslexic or kinesthetic learners.

Navigating the AGC is actually pretty user-friendly. Using the arrow, space bar, tab, and shift-tab keys let one move around fairly quickly, but many items can also be selected by using a hot key shortcut. The speech rate, pitch, and volume controls on the Speech tab page can be easily adjusted to the individual user's satisfaction. The AGC screen can also be magnified repeatedly and then decreased again. The domain, range, use of grid lines, tick marks, or none, and thickness of the graph can be adjusted to the user's specific requirements from the Plot tab page, allowing for further individualization.

The tab pages define the functionality of the AGC and each page has links to example exercises relating to that tab page. They include the calculator, speech, evaluator, wave, plot, and two data set pages.

Reliability and Flexibility

The AGC is accessible to all. The on-screen graphics are easily seen by a low vision student, and the graph can be listened to by using the audio wave feature. Print copies can be made using any standard printer using a variety of fonts including braille. The print copies with braille fonts can be copied onto swell paper and run through a tactile imaging machine to create a raised line graphic. However, the best way to create a tactile graphic is to emboss directly from the AGC to a TIGER (braille/graphics embosser) from ViewPlus Technologies.

A student listens to the audiograph sound of the parabola as she follows along on paper.

John Gardner assures me that they are working on adding matrix math to the AGC, and he now has a better understanding of why I have been so insistent on this. Work with matrices used to be shoved to the back of the Algebra II book because working with them manually was just too tedious for high school students. Now, with the advent of graphing calculators, work with matrices appears in Chapter 1 of Algebra I. As soon as we have the matrix situation under control, perhaps we can work on parent functions! I have always found John to be most cooperative, supportive, and greatly appreciative of all input, so I foresee the AGC adding even more features in the future, insuring that blind persons have equal access in all areas of mathematics.


I definitely recommend this calculator program for students taking high school algebra and beyond. WARNING: After exposure to the AGC, 99% of students are not satisfied to just graph linear functions. They are compelled to try and graph the most difficult functions their minds can conceive, especially becoming addicted to exponential and trigonometric functions.

Susan A. Osterhaus, M.Ed.
Secondary Mathematics Teacher
Texas School for the Blind and Visually Impaired
1100 West 45th Street
Austin, TX 78756
Phone: (512) 206-9305
Fax: (512) 206-9453