Are you sure he needs to learn how to focus, or does he just need to learn how to study? We found with our EG ds, that when he first ran head-on into challenge at school, he simply needed to have us (parents) give him tips on how to study. Things that seem simple in terms of digging for more info/etc actually weren't all that inherently obvious to ds, so we would show him how we would approach the problem and that helped tremendously.
OTOH, it also helped when he started being motivated by grades too
polarbear
