I would try to stay away from sports like baseball right now, do things where he can be active all the time, such as swimming, martial
arts, soccer, etc. I read that in a book that suggested that for some boys, the team sports where there is a lot of waiting is hard on boys. If you are concerned talk to the teachers, see if youc an talk to the school psychologists. Talk to your pediatrician, take him to a child psychiatrist. He is still very young, so keep that in mind too.