--> Find him some math friends! <-- He needs to own that "best math student" role. Find those other 1 in a hundred kids and get them together somehow.
Trying to force himself to be something he's not is definitely not the way to go. Trying too much to help him improve at sports just signals that you too think he should be better. He's just not that into sports. I don't think you can blame the 90th percentile processing speed - it's still 90th percentile compared with the rest of the population!
I hated netball at school, would panic and throw the ball to whoever shouted my name, which the opposition made a lot of use of! The answer: quit netball
Who needs that kind of stress?!
He's going to have to learn to stick out as the guy that doesn't like sports in your area, and instead be proud of being into the things he's into. Yes it sucks being picked last - get him into lots of other things as well that he can be first at, so PE isn't his whole world. Invite a couple of potentially friendly kids to a martial arts lesson. Start a martial arts club at school. Make friends with girls
Find or start a math club (or chess, or science, or whatever else he's into), talk to the school and see if they have any ideas for those 1 percenters. Can they have some sort of other roles on the teams …? (assistant referees or coaches? )
