This was (part of) the point with comprehensive schools, to do away with streaming and have classes by ability (on an individual subject level, so a kid might be great at reading but need help at languages, or whatever)[1]. This is actually even more important in later schools which often source their intake from a number of different schools with different emphases.
'Streaming' is based on the old idea that a person's educational 'grade' can be represented by a single number, some sort of aggregate. Which was why my mother was denied doing German or Latin or Greek, in spite of being top of the class in French and English, because she was poor at maths.
The problem with having classes by ability, of course, is the usual one -- money. It needs smaller class sizes and more classrooms and teachers because of scheduling problems. And it needs more work in trying to sort out timetables. Far easier to just assign a kid to a class where they will likely stay for the rest of their school life, and then treat all the kids in that class the same.
School intakes at different times of year? They used to do that when I entered school, I don't think it made any difference. The only way that would help is if you then had the school year staggered as well (so they always got a full year). But if you are doing that you might as well have ability grouping anyway, and forget about age (which is actually a lot less of a factor than many other societal ones, like the education and wealth of the parents).
I can see a plausible effect on children from when they were born in rural communities, though. For instance, a child born in the autumn would likely have a mother who was well fed for the last part of the pregnancy, whereas one born in spring the mother may have been short of food (or fresh food). I would suspect that things like that would influence the development of the child. But in urban and highly developed rural societies that will probably be minimal.
[1] It didn't work, because almost all 'comprehensive' schools were either a mashup of existing schools ("let's close one of the schools and put them together and call it a comprehensive!") or in some areas were just the old "Secondary Modern" schools renamed with the cream sucked off by the 'grammar' schools. Very few of them actually had the resources to implement a change in streaming practices. Those which did were good, but the majority gave the idea a bad name because it was never implemented properly (in other words a typical government programme).
no subject
'Streaming' is based on the old idea that a person's educational 'grade' can be represented by a single number, some sort of aggregate. Which was why my mother was denied doing German or Latin or Greek, in spite of being top of the class in French and English, because she was poor at maths.
The problem with having classes by ability, of course, is the usual one -- money. It needs smaller class sizes and more classrooms and teachers because of scheduling problems. And it needs more work in trying to sort out timetables. Far easier to just assign a kid to a class where they will likely stay for the rest of their school life, and then treat all the kids in that class the same.
School intakes at different times of year? They used to do that when I entered school, I don't think it made any difference. The only way that would help is if you then had the school year staggered as well (so they always got a full year). But if you are doing that you might as well have ability grouping anyway, and forget about age (which is actually a lot less of a factor than many other societal ones, like the education and wealth of the parents).
I can see a plausible effect on children from when they were born in rural communities, though. For instance, a child born in the autumn would likely have a mother who was well fed for the last part of the pregnancy, whereas one born in spring the mother may have been short of food (or fresh food). I would suspect that things like that would influence the development of the child. But in urban and highly developed rural societies that will probably be minimal.
[1] It didn't work, because almost all 'comprehensive' schools were either a mashup of existing schools ("let's close one of the schools and put them together and call it a comprehensive!") or in some areas were just the old "Secondary Modern" schools renamed with the cream sucked off by the 'grammar' schools. Very few of them actually had the resources to implement a change in streaming practices. Those which did were good, but the majority gave the idea a bad name because it was never implemented properly (in other words a typical government programme).