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by Maylene Bird

Cells: 

Teaching cell parts- I will attach the directions for making cell models on posterboard, no big deal, but gives some ideas.  See the Making Cell Models for these instructions.

I demonstrate the liquidity of the cell membrane (lipid bilayer) with ping-pong balls in a bowl of water and talk about the non-polar tails hanging down toward the water, imagine that another layer of ping-pong balls are under those balls with tails pointing upward, and note how they can move around and trade places.

I explain the embedded proteins in the cell membrane like a piece of raisin bread with the raisin being the protein and pointing out on both sides of the bread which is the membrane

I explain the lock and key mechanism of enzymes (the matching shape/ receptor proteins) with a child's toy shape finder where you put the shapes into the holes that are shaped the same.

Microscopes:

I teach the parts of the microscope and students have to demonstrate how one would put a slide on it and switch from low to high power, basically they pretend they are using the microscope and demonstrate it to me.

At our school, most of my class is unable to use a microscope so we attempt to make all the labs non-visual. 

Diagrams & Models:

We use raised line diagrams from the book and sometimes create our own diagrams.  Lots of explaining and reviewing. 

I try to find models to teach concepts when possible.  For instance I have used a large electrical cable to talk about nerves and how they are bundled.  I have small models of various animals and insects.  I have an ear and eye model that are very good.  I have a large DNA model that will unwind. 

I use modeling clay and play-doh to make models in some cases, although usually that has been in other classes.  I did use a clay model with embedded items to show the layers of skin with the hairs, follicles, and blood vessels.

I have to spend time on all the diagrams in the book.  I make the students look at them in class and explain them unless they are done too poorly to be useful.

Dissecting:

We dissect large frogs- get the largest one you can find for the student.  We have dissected fish in the past also.  The students are required to go over everything in the frog in lab, but some students are unable to locate inner parts without some assistance.  We use scissors in lab dissections instead of scalpels.  I base their grade on the frog lab mostly on participation.  I don't require them to draw anything for labs.

Measuring:

Try the Selph/Savi items for measuring, also FOSSWEB the official site for the inquiry-based FOSS science curriculum.

I currently use a 10 ml test tube to measure small amounts of water (it measures exactly 10 ml when filled to the top).  I have not used the Savi items yet, but just found out about them and plan to try them.  We have balance scales with weight sets.  If it's not adapted for lack of vision, I put a piece of tape under the pointer where the balance point will be.

That's all I can think of at the moment.    Hope it helps!

-Maylene Bird