My 6th grade is studying waves. Part of this involves making waves using slinkies. I know that slinkies are fun toys, so there’s a whole harangue about treating them carefully and not playing with them. Nonetheless, it didn’t take 2 days until someone turned one into abstract art.
Now, I know that slinkies aren’t expensive, but it’s the principle of the thing. Now I don’t have enough for all the groups.