Since we've been playing around with sounds, vibrations, and Newton's Laws of Motion lately, it seemed like a good time to show the kids another Steve Spangler experiment - The Screaming Balloon.
It's a fun boredom buster/musical instrument/physics lesson demonstrating Newton's First Law of Motion (an object in motion tends to stay in motion), and centrifugal force (not centripetal force).
If I understand right, when we did the bucket experiment, and T spun the bucket around in a circle, he was exerting centripetal force on the bucket, keeping it from flying off in a straight line, but the force he was feeling, of the bucket trying to pull away from his hand, was centrifugal force. But, check me on that, if I'm wrong.
Anyway, you don't really have to have a complete understanding of centrifugal, or centripetal force, to enjoy this experiment. All you have to have, is a hex nut, and a balloon.
Put the hex nut into the balloon, carefully blow the balloon up (you do not want to accidentally suck in the hex nut), and tie it off.
Then, grasping the balloon on the top, with one hand, spin it in a circular manner, as demonstrated by my four year old below, and listen to the music of the vibrations caused by the edges of the hex nut on the balloon.
My older girls were going to perform a screaming balloon duet, but while I was showing them how it worked, both balloons popped, and everyone became a little balloon shy - so you might want to consider heavy duty type balloons.
It's great to be a homeschooler.