I second the developmental optometrist as well. You can find one in your area at dt75's suggestion.
http://www.covd.org/ And then if he needs help beyond/without glasses he will probably need to see someone with a certification in visual/vestibular rehabilitation. This is what my DS5 ended up needing (without glasses). The therapy would help if he has writing issues or other assymetry with sports or balance as well. Our PT said that it should ony take 6 months to fix with 1x/wk with her and my working with him doing the exercises at home daily (about one focused hour per day). Good luck!
