We play D&D together at the kitchen table every evening that we are all together.
sounds like fun - can I come over?
If you child wouldn't object, perhaps the rock can only be moved if certian 'academic questions' can be answered while hopping, or similar.
Or, if I understand the game mechanics correctly, can special challenge cards be made up and won as treasure - so that if kid does 'X' then he gets 'plus one' on his die rolls?
I know it's early, but I'd hothouse typing if my son would have gone for something like this. 10 minutes of typing practice during the day adds 'plus one' to any 3 dice rolls that evening. Or 15 chess puzzles completed during school after his work is done adds 'plus 2' to the dice roll of his choice.
I was actually wishing for a 5-8th grade that was caried on entirely in this manner. Didn't find it though.
Smiles,
Grinity