It's not the schools themselves that are the problem, but the school culture. I have a friend who visits some secondary schools in Swindon and she is shocked how lovely new schools have been trashed inside.
If the culture of the pupils is one of apathy towards learning and violence it is often fed through to them by their parents/homelife. It is not the fault of the school.
A brilliant head and supporting staff can do wonders with school culture. But there can be a lot of resentment for authority with parents who did not have a good school experience.
Swearing, smoking, anti social behaviour in the class and out that is even intimidating for adult visitors means that the teachers who work in such places deserve admiration.
It would be cruel to send your child to a state school which has such shockingly intimidating 'street culture' if they did not fit in. A school is an important social environment, it's not just about education.
It is cheaper to send a child to Eton than to a youth offender's institution or prison. As that annoys me so much I think the key is to change 'sink' schools altogether, give parents school vouchers and if the local authority cannot provide your child with a school with a good OFSTED then they should pay you (plus make transport arrangements) to go elsewhere.
Then the teachers (paid a fortune and specially trained) can concentrate on the children who are left in these 'sink' schools (by parents who don't care about their education and there are lots) and give these children more one on one care,with smaller class sizes it could be more like a private school, especially if they improved their afterschool activities etc.
Standards would definitely improve if the head/staff gain a good rapport with these remaining children and their parents and then because of the better results, more people would be encouraged to go there.
Win win, no?