Low-performing students at private schools are having their estimated Cs and Ds bumped up to As. Stellar students at schools in poor areas who got As in their mock exams and have teacher-predicted As are being awarded Ds instead.
Do you have an example of this happening? It seems basically impossible from my understanding of the process.
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Edit: I think I understand how it can happen. A school with a cohort that is small, but large enough to get the algorithm, and a previously exemplary results, has an unusually bad pupil. I can see this happening in a subject like Further Maths where only good students take it