To get an ADHD diagnosis, you have to show the symptoms in two different places. So I tend to doubt that he would qualify. Also 6 year old boys can be very active. Especially when they have been stuck in school for many hours. They just need to get it out of their system. The best thing for him and you is to find something very active that he can do after school. If he can burn up that energy, he will be very different at home.