I have a kid that plays basketball and he's always running around the house jumping to see what he can reach and to improve his jump height.
Does a "thing" exist that has targets that he can jump for that vary in height that have an audible noise and/or tactile feel?
I could, for example, buy a bunch of small bells and hang them from strings on a pole. Each of the strings having varying lengths from long on one end to short on the other and then attach that pole to a door frame or arch in the house. However I feel that this isn't an original idea and that someone must have come up with a better solution than I've just described. (Or perhaps there's a product and my Google Foo is failing me?)