He is really advanced mathematically.
Not that I am an expert in teaching, but I do know math - find a good HS math curriculum and begin at the beginning and go as fast as he wants to. I was doing algebra on my own in 3rd Grade but did not see it until 8th grade in the school system. You can slow him down by taking side-trips into numerical methods at each step - first using pencil, then calculator, then computer programs. Once he gets into calculus, then you can start side-trips into classical physics and then QM. Statistics will lead to side trips into Chemistry. The big thing is making sure he builds a notebook of things to remember from each step AND does ALL the problems in the book - including the very hard ones - he should be intrduced to the idea of doing things in his head at night or while walking.
His reading will pick up as he begins to mature in math because he will have to read in order to understand more serious concepts. The older math textbooks from the early 1900s are sometimes more accessible to kids who read because that is how math was taught back then - and there is a lot less of the ridiculous "Mary has four Oranges and Two Apples. How much fruit does she have?" filler.
At some point he will move beyond your abilities and at that point he should find a mentor. A lot of school systems tap mentors from local universities or industry. There are also HS mentors. Another approach is to just take him to a local U and talk to the head of the Math Department about him taking college classes. But make sure he can do all the problems in the Calculus book before you do.
I would not waste any more time on the school system. You would not take an F22 to a Ford Dealership.
