Setting, streaming or all ability teaching - that is the question (to parody Hamlet).
Debate over the various different forms of how to group pupils for lessons has raged on for almost as long as the education system itself.
Suffice it to say I am against streaming - full stop. I was streamed which for a dunce in science meant I never got to grips with the subject. I can see a case for setting - the high flyers can be stretched more and the lower attaining set can find it easier to keep up in class. It only works, though, if there is an ability to move through the sets if a pupil suddenly develops a flair for a subject.
All ability classes are the most difficult to teach because the teacher has to make sure those who struggle are not switched off and high flyers are not bored. However, it is a fine judgement and there is research to show those who struggle in subjects do worse in low ability sets than mixed ability classes.
It really all depends on the school, the ability of the teachers and the confidence of the head in their staff to deliver whatever method the school decides upon.
Which is why it is better for politicians not to pontificate on what should be going on in schools in this area.