Calculus did me in...

I took calculous in community college. My professor spent as much time explaining the origin of calculus and how Newton developed it, as he did teaching the actual formulas, methods, etc. It was a fascinating class, maybe the best math class I've ever taken because it wasn't simply "here's the formula, now memorize it" but instead we learned why it actually mattered.

I wish I could remember his name (or find my transcript). It was back in the 80's so I doubt he's even alive anymore.