Sunflwr,
While I appreciate your concern for your son, this is so much better than having him running on the streets, getting into street racing (which is much more dangerous), drugs, or other things that are a lot worse than racing.
Having a thirst for this at his age is wonderful.
He will learn a lot of life lessons, such as sportsmanship, ethics and many more.
I hear what your saying about it taking priority over school and homework, those must come first.
Anyway, enjoy and if you need any advice or help let us know.