Sounds like you just had terrible professors because most of mine were good and we learned quite a bit in classes, at least I did. I distinctly remember one professor who, every class, would meander discussion over many topics then find a way to bring them all together at the very end, crystalizing all of these disparate thoughts into one cohesive theory. And he did that every single class that semester. It was a marvel to behold.
I remember my calc teachers, married, last name gulick, university of maryland. The calc book was sold as the same book for calc 1/2/3. The couple, gulick were the authors. Every semester they released a new edition, the only thing that changed was the problem set numbers. So, if you took calc 1/2/3, you spent $200/semester for the same fucking book.
Magical times.