I just had to post this picture of Jeffrey's school project. I think it would have been cool to see a classroom full of each students projects. The assignment had a list of items to use to move a tennis ball; some of the items required was an inclined plane, a pulley, and all 3 classes of levers. He used a rat trap to do the final projection of the ball. (Here it had just released from the cup.) I contributed the spool for the pulley and the shish-ka-bob sticks to elevate the pulley. We called it the Ratapult.