So a LOT has to do with the home environment, the child's activities, and their attitude about learning and life and what matters to them.
Isn't that the truth!
I think that the home environment and its cultural attitudes to work and study make way more difference than the enormous amounts spent on public education.
After a certain point, that is, obviously if a school is underfunded to the point of not having enough classrooms, books, computers or not able to hire master teachers then all bets would be off.