My inclination would be to look first to possible accommodations regarding reduced work load, to virtual school, or to some kind of hybrid (so he can continue with orchestra, for example). Virtual school has some additional pluses, in that it is more likely to have some self-paced aspects to it, and he will likely save on a lot of in-school non-instructional time.
For instance, a modified schedule could consist of a couple of hours in school, to attend orchestra, and whatever academic most benefits from face-to-face teacher & classmate interaction, then early dismissal to finish the remainder of his classes online.
