I'm sorry your kids are having such a rough time. Have you asked the school psych or school SW if there is a social skills group they could join? They could learn some basic skills to help them interact better with the other kids and may even make a friend or two in the group. At the least they will probably be able to find someone to eat lunch with or become part of a "lunch bunch" once a week. If they are in a school for highly gifted there should be kids who "get" them. Maybe this will give them the support they need to find them. Good luck!