Today we made Oobleck!
It had been a few years since we did this last, so most of the kids didn't really remember it. They all had so much fun playing with it and handling it different ways for different effects.
It kept them busy for the better part of 2 hours...
...and anytime one of my children uses a term like "non-Newtonian liquid" and actually understands what it means...I'd say that's time well spent.
It really is such cool stuff. Every time I put my hands into it I had a hard time walking away. Brings out the kid in everyone, I'm sure.
Worth noting: Contrary to how these photos probably appear, clean up was not bad at all. The dry stuff flakes off and sweeps easily, and a wet rag does the rest.