KADmom,
Those are really good score. Those indicate that he is >90 percentile of average 8th graders. Your DS sounds like a perfectionist and does not want to make mistakes. May be he is worried that he may not do as well after grade skipping.
Anyway, we are more than half way of the school year and the middle school usually offers more opportunity for subject acceleration. Some schools have pre-AP classes which are 1 grade above level and some schools have TAG classes that are 1 1/2 grade above level. You should inquire what your middle school and high school provides and go from there.
May be you should discuss with the middle school counselor to see what they can do for your DS.
