Education comes down to the parents, and social values. And, please note, I am not commending the government for their stupid comments and decisions.
I am talking about the parent of the individual kid.
At private schools, the majority of kids are from a home where education and "drive" are high on the agenda. Otherwise, the parents would not be forking out the money for a private school. In this environment, you will find educated parents who will teach their kids things (be it PC related, how to read the stock market report, that "Heidi" is a great book, etc etc etc).
At the majority of the schools where learning is a non-event and failure high, the home structure is not one of learning (be it because of an illiterate parent, a parent of poor standing or a case of parents never being at home).
In the last case, the guardian is at fault (if there is one) or the social fabric of society - but not the school.
Education, she begins at the home.