marrieddad I guess the main model of selection is the grammar school system. I went to one myself and it gave me opportunities that I wouldn't otherwise have had. However, I totally agree that it can be demoralising when children fail the 11+ and their brighter friends go off to other schools. I'm not keen on putting a lid on children at such a young age, and I know that research shows that some children can feel labelled as 'not bright'. Then you can have cases of self-fulfilling prophecy: I already know I'm not the brightest, so why try to be academic? Grammar schools are wonderful for those that pass, but do nothing for those that don't.
So, let's say we don't divide children at all- let's have mixed ability classes in comprehensives. Well, I've taught mixed ability classes and, good grief, that is challenging. Trying to stretch to the top and give extra support to the weakest (in a class of 30 in one hour) is really not easy. I'm not sure that method meets the needs of children either.
That only leaves us with setting and streaming. I am totally against streaming which places children in the top, middle or bottom set for everything, because very few pupils have the exact same affinity for very different disciplines such as Maths and English. Setting does work, or it does for me, especially if it is mobile and pupils can move up and down within the academic year. The problem is for those in the bottom set, who may feel disaffected by this. I always tell them that it is better to be supported than to be in a class where they struggle. For me, a good comprehensive with setting would be my first choice.
One thing that would make a massive, massive difference to the quality of educational provision in this country is smaller classes. I am utterly, utterly convinced that this is the case. It's not going to happen because there is no money! I think that, after behaviour, class sizes make the biggest positive difference.
I like the boarding idea. There are fines for parents who don't care if their children truant school constantly, but there isn't much schools can do about home aspects that don't directly affect the registers, unless there is abuse. For example, when a child regularly turns up having had five hours sleep and no breakfast but doesn't care/ their parents tell them they don't need to go to detention / their parents don't ever bother turning up to parents' evening. All of these things make it incredibly hard for teachers to convey the importance of education, because the children aren't intrinsically motivated and their parents don't help matters.
That was a long post. Sorry OP: not quite on topic, but still interesting to explore.