@practicallyimperfect: "I don't want him having to sit in class after class, with all the attention being on the hideous disruptive kids. If he is bright he will be virtually ignored, as he is a guaranteed C grade.
I have worked in a few state schools, and have many friends that work in others. The money, effort and time goes to the middle ability D/C kids, or those with SEN or EBD. They needs as many Cs as possible. There is a lot of awful behaviour."
This is so telling, coming from a teacher. It's also my experience, and the experience of many of my friends. State education - at secondary level, anyway - is not what it was. This is a generalisation, and maybe not true of all secondaries, but they seem to spend a lot of their time getting the borderline C/Ds up to Cs and most of their energy dealing with disruptive behaviour.
As for people who said they want their children to be able to get on with people from all walks of life, I'd agree. Except I'd replace "all" with "most". Do you really want your kids mixing with children who are physically violent, verbally abusive, foul-mouthed and racist? If so, then your local state secondary will probably meet your needs.