They certainly seemed to be. I think in hindsight it was more the jump from GCSE level. It's not so much that A levels are difficult or advanced, more that GCSE's were so simple, and in no way prepared us for A-Levels. It certainly was a bit of a shock, having to actually attend lessons in order to understand it.The A'levels in maths and physics were harder than the degree I think. Never used it in real work but handy sometimes to work thinks out...especially some of the structural beam calculations for example.
Looking back I think I was definitely smarter back then!