...which means it could be really easy or it could be a total bitch - it completely depends on the teacher.
This. I took AP Calc as a Junior, which should've been easy, but the teacher also happened to be the bitchy track team coach (Our school is in a rural town filled with hicks, so there's not too much need for book learnin).
She went over shit in the most complex way possible, and I ended up as one of two students, in a class of about sixteen, to pass the AP exam. Even though it was just simple integrals and derivatives...
Then I took a Dual Enrollment Calc II course at a technical college, and it was the easiest class I had that semester. The teacher really matters when you get up to anything complex.