If you are not comfortable with him being sent back to pre-k I would definitely say something. From the reasons you stated they gave my DS5 would be sent back to pre-k, though his age wouldn't permit it. I go into the class and watch him. He stares off into space, does his "projects" very slowly and hardly ever finishes them. I believe that he isn't interested and I don't really blame him. However this has led his teacher to believe that DS doesn't need more because he's not showing him he wants more. It is sort of a catch-22.
