Freshman calculus. It was a daily class, 2 lectures and three smaller sections, one every day. You had to keep up and stay with it every night.
I worked three nights and Saturdays and constantly found myself behind and bewildered.
I found a classmate who was willing to help me out after class once or twice a week and that helped get me through. I only got a C.
For Calculus two, I took a class with two double sessions and one single session that removed the need to keep up every single weeknight.
This was a long time ago before the age of computer-aided instruction. My son is a freshman and is able to go over problems by logging into his teacher’s home page.