My son also had to do the gum chewing for a few years. It really helped to keep him focused. Also, up until this year he had a cushion for his seat. It was triangular and kinda bouncy. It helped tremendously to keep him in his seat, because he got the sensory stimulation while sitting down.

We worried a little about him using it all the way into the 6th grade as he is fully integrated and thought he might be teased. We left the option up to him. He said it was actually a "friend maker" as the other kids would want to take turns using it too!