I was working with my fifth grade daughter last weekend on her science project for the semester. She had to come up with a source of Home Made Energy to move an object a total of 10 feet across the floor. It did not sound like such a big deal when we first looked at it but it became a challenge that we had to conquer. We ended up going with a solar energy solution. We put 2 small solar panels on top a piece of wood with wheels on it. The panels were connected to a tiny motor that drove a fifth wheel under the piece of wood. It made the 10 feet in about 6 seconds.