Tops and Bottoms

Everyone knows to have "free cupboard" in the kitchen for when you are cooking. But I never thought to organize it a little.
Put out Tupperware, with matching tops scattered around. Have them match up the tops to bottoms. Then you can build a tower, and knock it down over and over. Finally, make sure they take the tops off and put them away.

This wasn't a favorite of R's, she had a hard time fastening the tops, so she got frustrated, maybe I'll try again in a few months.