Re contextualising GCSEs DS1 went to a state comprehensive which is outstanding and has a higher progress 8 than the national average and the local average. My son is testament to being predicted certain grades off his year 6 SATs and absolutely smashing through them through sheer hard work.
As a comparison, the local selective grammar but non-fee paying had 98% of students achieve maths and English grades 9-5 grades compared to DC's school which scored 59%. The local authority average is just 42%.
When the History GCSE class is mixed ability and my son is predicted a grade 7 (he got a 9) and others in the class are predicted a 3, where do you think the staff concentrate their efforts? Of course it is trying to get the grade 3s up to a grade 4 not only so the child has more passes at GCSE but also the school does too. And rightly so.
This was the same for languages where they combined the lower and higher ability classes for year 11. A disaster for the higher ability with the lower ability ones needing so much of the teacher's time and attention. Only my son and one other student were singled out for a high grade. He got an 8.
Only English, maths and science were setted all the options classes were mixed ability. In maths he was in the 7-9 group, "top set" maths was the next one down and meant anyone going in for the higher paper.
All students applying to Oxbridge still have the A/A predicted grades for A level, they aren't doing someone a favour. No talks ever mentioned Oxbridge at Ds's sixth form. They intake anyone who has grade 4s but some subjects such as science and maths need a 6 or a 7 for further maths. But Ds1 was chosen to be on the Cambridge outreach programme hence why we found out a lot. Ds got the equivalent of one A and the rest were As for GCSE. There is no information on the sixth form's website about being a Cambridge HE+ college.