Sorry if I'm repeating some things that have already been said... I'll be honest... I didn't read every post :-)
I just wanted to say that my dad and I were just reminiscing the other day about how first grade was just hell for us. We were not ready at 6-7 years old to be away from home for 7-8hrs a day. Academically and socially we were fine but a long grueling day of desk work was just way too much for us.
I don't know how your school is but in 3rd grade sometimes there is a lot less recess, pe, library, change of scenery, etc... than there is in first grade. It's usually a gradual change but when you skip grades I bet it can be a huge adjustment.
Have you considered doing part time homeschooling? Especially since he's so young and a full day of school can feel like a LOT.
They very long school days we have nowadays is one of the reasons I'll be homeschooling after kindergarten (if not for K as well)
Just a thought!
Good luck.
