Oh thank you! That makes much more sense. I had not clicked the button that said "someone else can claim you as a dependent." When I go back and click that and then click the "no one will claim" button on his return it looks like he loses the stimulus benefit but keeps the tuition tax credit. Which sounds more what I would have expected.
But I will also go through the tax return more to make sure, and look at the state return as you suggested.
