Not too easy. Not too difficult.
He was certainly knowledgeable about math. He was not shy about telling us. But I don't think he was suited for teaching any normal students. Only the math nerds. The class was very slow moving, because he had to take the time to explain every single concept down to its very core, which is why we were so behind. I found his explanations interesting, but they were lost from my noggin in summer as well. If you don't want to become some kind of math scientist in the future, I'd recommend getting pre-calculus class that doesn't have him as a teacher.
The thorough explanations on every math concept was interesting. I don't think I've ever had a math teacher like him. I learned pre-calculus, and also, the importance of leaving behind work...
Hours per week:
Advice for students:
It'll obviously depend on the person, but you must study. This applies for every course, and this one as well. Study, study, study. You don't have to study for 5 hours or so, just until you feel it has been lightly burned into your brain. Emphasis on lightly.