The Math/Science magnet programs that some states offer (Illinois, VA, ??) seem best for him, but I think you'd have to already live in the state in 8th during the application process. In CA it seems like there would be a lot for these mathy kids. Does he also have interest in STEM activities like Robotics? That may keep him busy in a way that involves a team.
To me, sounds like Exeter would be good for him. With the numbers at Exeter, does every student really play a sport (and not get cut?). Do they have any non-competitive sport option?
I'd also start researching math magnet programs ASAP....maybe there is one he can get into if you move (and they may sometimes be free).
@payn4ward Thanks! Went to ped a couple days ago and got a similar MenB shot...the other one, which requires 2 doses (I think a month apart, but she said it's flexible).
And thanks re the testing...he will take the SAT Math2 tomorrow and see how it goes. Not sure if he should try the SAT in November (he feels ready for that now, but will have little additional prep time with fall sport), or wait until March.