I've seen this discussed, but I only just clicked how much harder it is. DD is revising, and has been given a maths past paper to do, but no answer booklet. So she asked me to mark it.
I have maths A level, but struggled a bit 
Differentiation, 3-d trig, factorising quadratic equations??! I'm sure I didn't do any of that at GCSE (in mid 90's). Is A level harder too?