AP Calculus BC is often said to have one of the highest 5-rates among AP subjects — but in reality, it’s one of the most conceptually dense and mentally draining exams.
For me, it was by far the hardest one I took.
My first shock in high school came when I got a B in Pre-Calculus during freshman year — the first and only B I received in all of high school.
That single grade hit my pride hard enough that I promised myself:
“I’m going to take AP Calculus BC — and I’ll get a 5, no matter what it takes.”
So during the winter break between freshman and sophomore year, I made an insanely intense plan — and actually followed through.
It was so exhausting that I almost burned out, but it built the most solid foundation I’ve ever had for math.
My goal was to cover everything from the Korean curriculum equivalent of Math I, Math II, and Calculus in just about two months.
I used a series called 개념쎈 라이트 (Concept SSEN Light) — thin, stripped-down concept books that summarize only the most essential formulas and logic.
Every day, I studied 8 hours of math, filling dozens of notebooks with solutions.
I never wrote inside the textbooks themselves so I could redo them 3–5 times each.
It was a painful process — but it made me fluent in the logic of functions, graphs, limits, and derivatives.
That’s why I was able to take the AP Calculus BC exam without any tutor, online course, or academy.
If you don’t have access to Korean concept books, don’t worry — you can recreate the same system: