I’ve take Calculus 1, 2 and 3 along with Differential Equations in College.
Kids today need to understand that you can’t slack off in these higher level math classes. It requires determination and effort. You get behind a few chapters or classes and you’ll be in real trouble to catch up.
Yep, you can’t get behind in math or foreign languages and then cram for the test. Once I learned that, I did OK in college. Never went beyond the first course in differential equations, though that came in handy later when I took a physical chemistry course.
Naturally, I have long since forgotten most of what I learned in college. Sometimes I think about digging out my old calculus textbook and seeing if I can work my way through it again for mental exercise.