Have you met with your DS's first grade teacher? I think that might be a good place to start.

Our GT services didn't officially start unti 2nd either, but DS's teacher made a special referral and DS was invited to come spend time with the GT 4-5 graders a few hours a couple days a week. It did solve our problems since DS is generally pretty easy-going. Obviously, this is too little to meet every kid's needs, but it was something that helped us.