It varies my first year Computing teacher at high school (15) was very good but she left and a maths teacher took over but by that point I was learning faster

It varies my first year Computing teacher at high school (15) was very good but she left and a maths teacher took over but by that point I was learning faster from books than he was. But because I was in the lower stream CSE (the exams for those supposed to leave at 16) they wouldn't let me take Computing at A level - even though I scored the max level in computing and maths.