when all else fails...baths.
Speaking of what you buy at the thrift store...I found a bunch of (new) craft-foam shapes there the other day. Like the stuff you buy at the dollar store and that cheap foam things @ craft stores are made out of for kids.
it sticks to the side of the wet bathtub.
Putting 20 small foam flowers in a bath tub bought me an hour of "sit next to the tub while reading my kindle" time this weekend.
Also, bath is an excellent place to do stuff like paint. If you mix shaving cream with poster paint, in muffin tins, and hand it to a naked chld in a tub, there is no mess...you rinse off the tub and the naked kid and...ta da, all done.
(or, if you're not that brave, tub crayons)