Captain of the Math Team.
I wanted to mention something about your son being Captain of the school Math team.
I think it is important that you recognize the razzing he gets from his peers. While it is okay to point out that his teachers find him to be a superstar, let him know that he should first being doing these things because he wants to.
Being one of the smartest kids in the school will not usually find him with the in crowd, but I think it is important that he not do things just to get teacher approval.
In my case, since I always had difficulty fitting in, I was more than willing to seek the praise of adults. This led to a cycle of doing things for the teachers, and further making me an outcast with my peers.
What should you do? I think you should let him know that he is indeed special, you love him very much and that he just needs to be willing to seek out other kids who will respect his intelligence. Convince him to be willing to continually seek out friends, and that you know it will not be easy.
The danger is that if you do not actively encourage him to keep looking, putting the onus on him to find people while acknowledging the difficulty, he might end up falling into a relationship for all the wrong reasons.
Let him know that his skills make him a great friend to have, and just because a lot of the kids razz him, does not mean he should change to get other kids to like him. He needs to know now (in my humble opinion) that he does not need to jump in head first the first time someone seems to want to be his friend.
The point I am making rather ineptly is that the best message you can give your son at this point is to acknowledge the way he feels. My parents seemed to constantly ignore or trivialize my complaints about nobody liking me. Yes I can still be a pain to this day and true the psychologist told me I should remember that I am somewhat (Okay drop the somewhat) a high maintenance friend.
But the point is that when I am willing to recognize my weaknesses, I am better able to handle the person-to-person interactions. Yes there are some of the civilian workers here that will always give me a hard time, at the same time there are a few that openly recognize my talent and willingness to work and those are the people I should worry about.
The others I still have to deal with but I do not expect much in the way of recognition from them