Toy Fish that Comes to Life

Here is how you can make a toy fish that will come to life in your hand.

Equipment Needed

1 pair of scissors
Celluloid or sheet plastic

The Experiment

Cut out the shape of a fish from a piece of celluloid or sheet plastic.

Make sure its tail is reasonably large (Fig 1)

Rub your hands together so that they are warm.

Extend one of your hands with the palm facing up. Using your other hand, place the fish on your palm.

After a few seconds, the fish's head and tail will curl up (Fig 2)

How It Works

The underside of the celluloid or plastic sheeting warms in your hand and expands. However, the top of the fish does not get any warmer and therefore does not expand. This causes the fish to curl.