Drexel set up a simple machine. “Here’s an experiment you can do later. Take a small ball and a ramp—a piece of cardboard works great. Hold the ball at the top. That’s potential. Let it roll down. That’s kinetic. Try using different heights to see how it changes the speed! I’ll give you a hint. The more potential energy it starts with the more kinetic energy and speed it ends with”

“To make it more fun,” Drexel added, “build a chain reaction! Set up dominoes or paper cups for your rolling ball to knock over. That’s mechanical energy doing work!”

Drexel moved to a chart. “Let’s review! I’ll give you a situation, and you tell me if it’s kinetic or potential. Ready?”

He pointed to a skateboarder at the top of a ramp.

Liam shouted, “Potential!”

“Now the skateboarder zooming down the ramp?”

Chance did finger-skating tricks. “Kinetic!”

“How about a rubber band stretched tight?”

Liam flexed. “Potential!”

“And one flying through the air?”

Both shouted, “Kinetic!”

Drexel nodded. “You got it! Whether it’s a boulder on a cliff or a cheetah in mid-sprint, mechanical energy is everywhere.”