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Alyce Glauner Grant Community Academy
145 S. Campbell Ave.
Chicago IL 60612
The main objective of the Mini-teach is to show Primary students that
there is electricity in all matter.
Van DeGraff Generator 5 Balloons
Rabbit's Fur Glass Rod 12-18 inches long
Plastic Rod 12-18 inches long Piece of String 15cm long
Tape 3 Pieces of String 35cm long
Small Paper Scraps Salt and Pepper
Puffed Rice Mashed Potato Flakes
Small stream of running water (if available)
Enough for the class or group-pop cans, 1 in x 1/2 in, aluminum foil strips
combs, foam plates, foam cups, pie plates.
Using the Van DeGraff generator place the pie pans face down on top. Put
the generator on have students stand back and watch the plates sail off. If you
have older students, they can form a chain to see how far out the charge will
travel. Always discharge the generator with a stick when you turn it off. The
students can also try one at a time to place their hand on the generator, while
they stand on a milk-crate to insulate them from the ground. See what happens
to their hair.
After the demonstration, the students go to stations. Your options to set
1) Balloons-Tape one end of 15cm string to a table top. Charge a balloon by
rubbing it with the fur. Hold the balloon over the thread, don't touch, the
thread should move towards the balloon. Tie a 35cm string to one balloon, hang
it on something freely, tie the other string around another balloon, and hang it
about 5 cm. away from the first. What happens? Charge one of the balloons,
what happens? Charge the other balloon, what happens? The first time they
should attract, the second time they should repel. Charge a balloon and see if
you can get it to attract to the wall. Tie the last 35cm string around a
balloon and hang it up or tape it to a table. Charge the balloon and place your
hand close to the balloon, don't touch, it should follow your hand.
2) Combs-Comb your hair very hard. Place the comb near one of the above
items. The static electricity will make the item attracted to the comb. Try
with a number of different items. Come up with your own ideas. Comb your hair
again and place the comb near the running water. The stream of water will
either repel or attract (the water really moves).
3) Electroscopes-Rub fur on the bottom of the foam plate, place a pie pan on
to the foam plate. Lightly touch the pan to charge it. Bring the charged pan
over to the Electroscope. The leaves of foil will repel because of like
4) Make Electroscopes and Electrophorous-Glue a foam cup on top of a pie
pan, as a handle. Use two foam plates, turned upside-down, to rub the pan on to
charge it. Tape a pop can to the top of a foam cup. Take the foil strip and
loop it loosely over the tab of the can.
The assessment would probably be teacher observation. Did the student
follow directions? Did the student participate in stations? To what extent was
his participation? You could also have them record their observations and
results in their journals. A rubric would be easy to make for this exercise
4=followed directions, used all stations provided, recorded all
3=followed directions, used most of the stations provided, recorded most of
the information requested.
2=followed most of the directions, used some stations, recorded some
1=followed some directions, used few stations, recorded little information.