A Styrofoam plate is rubbed with wool and the foam plate becomes charged with static electricity. The electroscope is placed on the charged foam plate and the charge disperses over the aluminum pan and ball. The pan and ball repel each other, because they both have the same negative charge. When a finger touches the ball, the charge is drained from the ball and it becomes positive. Now, the positive ball becomes attracted to the pan. When it swings back and touches the pan, it becomes negative again and repels. A finger touch makes it positive again and it goes back toward the pan. This cycle continues until the pan is discharged. This teaches children about the charges and flow of electricity.