The solution COULD be very simple - - weed ou the dispurtors (send them home for good) and teach only those children who are civil and wish to learn. Why do I suspect that the education mafia in the UK, like here in the US, would have a problem with that?
I appreciate where you're coming from here (and no, I don't think the US or UK would go for it), but I think it's a better option to restore a teacher's right to administer serious discipline. I believe that would result in far more civil, educated kids than just sending the bad ones home. (Of course, we'll still need to do that too, only hopefully less freuqently.)