In any event, R. decided to take matters into his own hands and take him swimming whether he wanted to go or not. And he apparently protested for most of the time he was in the water, but came out happy and calm. By the time he got home, he wanted to extract all the puzzles and all the pieces of the puzzles (a couple alphabet puzzles, a couple number puzzles, some shapes puzzles -- all puzzles with each piece going into an isolated slot, most of them magnetic) which were mixed together in his toybox and put them together. R. and I took turns helping him identify which piece went with which puzzle; once he knew which puzzle, he was pretty good about figuring out where the piece went, but sometimes needed help getting the piece oriented correctly. Then he wanted to put them all away on the shelf where they belong. Distinctly different from where they _have_ been stored in the toy box.
R. is going to try taking him swimming more or less daily for a while and see if that helps. He was much less chaotic and seemed a lot happier. I'm going to see if I can convince him to ride his bike tomorrow after school around the neighborhood with me and/or go for a run with me around the block.
Maybe I'll suggest jumping on the bed a little, too. :-)