I have numerous friends who are teachers and they all consistently say that the biggest problem is poor parenting. Primarily disengaged parents or parents who don’t value education.
Of course this is the elephant in the room because no politician is going to blame parents.
It seems to me that all the chat up-thread about schooling vouchers and parental choice are entirely missing the point. The children of engaged parents will probably do ok anyway. It’s the bad parents that are the problem.