MofN you nailed it! I don't know if they are ready for him.
My problem right now is that I don't know what would be best. I know that in DS's strongest areas much of the material seems downright insulting. I don't want to ask him to do stuff that he has been doing for over two years now. To me it seems cruel to put a child who can reason that air takes up space in a classroom that is learning that wind is moving air. In class differentiation might be ok in math but I doubt it would work in science. If I had to guess, I would say DS is working at a 3rd to 4th grade level in that area. I just have very little idea on how you begin to bridge that large a gap.
Right now DH & I plan to work on gathering more information. We want to try & get copies of the math & science curriculum for 1st & 2nd grades. Hopefully this will give us more perspective on the schools expectations. We also want to try & sit in on a couple classes. Maybe once we do that I will have a better idea about what needs to be done for DS.