Hey all. I am teaching younger kids, ages 7-9, about physics this summer, and I was wondering if anyone here is a teacher in elementary school or middle school, or has advice on cool activities to do. As far as the physics goes, I don't think it will be a problem since so much of physics can have a mystical aspect, but I would welcome cool ideas and experiments. Mostly what I am wondering about is if there is any tricks or tips to keep everyones attention occupied. During breaks, are there any good mind riddles appropriate for this age that I could ask? What about other activities to do while resting from physics, since not even the most dedicated can take four hours of physics without breaks?