My kids have an hour to an hour and a half of "Quiet Time" in their rooms every afternoon. They can draw, read, play with quiet toys, listen to music, nap, whatever they want within reason. I usually let one of the boys "sleep" in my room during quiet time so the other has their room to "sleep" in. When its Little Man's turn to be in their bedroom he usually cleans! How sweet is that? He'll take a notebook, pen, pencil and books with him but he almost always ends up cleaning the room instead. And he's only 4, well he'll be 5 at the end of April, sigh.
I really am spoiled ;) (and so is M, lol)