I just ordered the Python book recommended above, for DS10 -- I asked the school-allergic boy what he wanted to know (avoiding the "learning" word although I told him if he didn't pick something for the summer, I would pick for him), and he said that something in Minecraft uses Python and he wants to know that. Score!
I looked at AoPS, but at $275 a pop it's just not going to happen. Even if there weren't 35+ people on the waiting lists for both summer classes.
Also trying SpaceChem as recommended above, though I'm not sure if it will be for me, DS or DD.
