Also, I have already found my son a high school. It had a gifted program ( a rarity in my state) where you can consolidate some grades, so instead of taking five years to complete it can take three years; then the child can take early uni classes to shorten the degree once at uni.

I know it's early times, but I couldn't imagine my son losing his maths abilities. He has had them since he was a baby, and they're only getting incredibly stronger.