When I used to substitute teach for music classes, one of the kids’ favourite instruments (and, to be honest, mine too!) was the boomwhacker. Boomwhackers are a series of colourful plastic tubes of different lengths that are tuned to different notes; they produce sound by striking against the ground or each other. While most of the music the kids made was simple, it turns out that, with a little cooperation and a lot of coordination, significantly more complex performances are very much possible!
Imagine what those practice sessions must have looked like–bouncing, rolling boomwhackers everywhere!