The Wave Machine
"In this experiment, you will create a wave machine using tape, skewers, and gumdrops. Observe what happens when you tap one skewer. It creates a disturbance that twists the tape, causing a disturbance in the skewer after it. This creates a wave that bounces back when it reaches the skewers. When a wave hits something solid (that they can’t move through) they reflect back in the opposite direction."