Just started year 12 and doing OCR Chem and biology. According to my teachers, to get an A*you need to get 90%. For an A, 80% and a B 70% etc etc. Idk why they’re so high.
Just checked the grade boundaries for the 2019 exams and biology is surprisingly low for an A*, it was 185/270 for an A* which is around 68%. However for chemistry it was 230/270 so around 85% for an A*