I teach at the type of school that MNers love to hate. It is a very oversubscribed CofE comprehensive. It achieves excellent results because the type of families able to access the school are generally heavily involved and invested in their children's education.
Out of a class of 28 Year 8 students, I had requests for appointments at parents' evening for 25 of them. One of the common questions asked was 'What can I do to help my child?'
Like a lot of secondary schools, it is going through a financial crisis. There are no textbooks to support the new KS3 courses. Teachers are often teaching (not great lessons) way outside their specialism. The pupils will continue to get good results because of the type of family involvement. Parents ask about the course we follow so they can buy a textbook of Amazon to support class work. They print off summary sheets and revision sheets from the school's VLE as we can't afford the photocopying.
The number of students who obviously don't give a sh*t about education is tiny (1 or 2 per year group). Often, there is little to nothing you can do with those students. Luckily, there are very few of them in our school.
The school has a very good reputation locally for behaviour and results. It is a virtuous cycle which means the school can attract (relatively speaking as the 'pool' is incredibly small) the best teachers.
I'm not arguing that this situation is 'right' or socially acceptable. Having a school that is only accessible to parents willing to jump through all sorts of hurdles is highly questionable.