Same here. That's how I learned it as well. That said, I didn't really "get it" until I was well into the class. I still remember that "aha moment" very vivid

Same here. That's how I learned it as well. That said, I didn't really "get it" until I was well into the class. I still remember that "aha moment" very vividly, even though it was in 1992 or so. I was sitting at a table in the school library working on a problem about a pool being emptied while it was raining and my brain said "Holy crap! This is just about how fast things are changing!". With all of the proofs, graphs, etc. things were never put into such a simple statement. The end result of months of flailing followed by the "aha" was a grade of C for the class AND being the only one to get a 5 on the AP test. EDIT: As a fun corollary, I really hated Calculus class in high school. Ironically, I ended up getting a Masters in EE, so I ended up spending the next several years doing Calculus in > 50% of my courses. EDIT EDIT: Also fun to note was that Calculus was only offered to Seniors at the time and required 4 years of math beforehand: Algebra, Geometry, Advance Math, and Trigonometry. That meant you had to double-up on math in either Sophomore or Junior years, which basically limited class size to a small handful of people.