# Teacher Activities

A partial listing of the teacher activities is contained here.

 Coin in the cup Push it Around Strong pull, weak pull Funnel magic Antigravity pail Straw atomizer Magic tablecloth Test your strength

### Coin in the cup

Material: Index card, coin, drinking glass

Place the card over the top of the glass. Put the coin on the card so that it lies over the opening of the glass. How can you get the coin into the glass without touching the coin or tilting the card? Why does this work? Does it matter how fast you do it?

### Strong pull, weak pull

Material: Book, strong string, thread

Tie the strong string around the book. Cut two pieces of thread. Tie one piece to the string on the front cover side of the book. Tie the other piece to the string on the back cover side of the book. Pick up the book by holding one of the pieces of thread. The book should hang from the thread and the second piece of thread should be hanging beneath the book. Hold the second piece of string too. Which string will break if you pull strongly and very quickly? Which one will break if you pull slowly? Try it. What happens? Why?

### Antigravity pail (Do this one outside, if possible.)

Material: Tin can, string, nail, water

Punch two holes at the top of the can, one on either side. Tie the string through the holes. Put a few centimeters of water at the bottom of the can. Swing the can in a vertical loop. What happens? How fast do you have to swing the can to keep the water in?

### Magic tablecloth

Material: Piece of paper, objects from the kit

Place the piece of paper on a smooth surface. Place some objects on top of it. How can you get the paper out from under the objects without moving the objects? Try with objects of different weights. Is it easier to do if the objects are heavier?

### Push It Around

Material: Foil-wrapped weighted cups

Start with the two equally weighted cups. Put the wide end down on the table. Give the two cups an equal push. What do you observe about the motions of the cups? Now try giving the cups unequal pushes. What is the motion now? Why are they different?
Now use two cups with different masses. First try the equal push then the unequal push. What can you generalize about force (push or pull), mass and acceleration (change in speed)?

### Funnel magic

Material: Funnel, ping pong ball

Place the ping pong ball in the funnel. Try as hard as you can to blow the ball out of the funnel. Try pointing the funnel in different directions. What is happening?

### Straw atomizer

Material: Drinking straw, glass of water, scissors

Cut the straw almost all the way through, about 2/3 of the way from one end. Place the long end of the straw in the glass of water. Bend the straw 90 degrees at the break. Blow through the other end. How does it work?

### Test your strength

Material: Large sheet of paper(newspaper size), ruler

Spread the paper out on a table top. Put the ruler under one part of the paper so that the free end of the ruler sticks out from the table. Push down quickly on the ruler and try to lift the paper. Why is it so hard to lift? Can you think of a way to lift the paper easily?