Not too easy. Not too difficult.
I personally found the content to be engaging and fluid.
I'd say the most notable recurring topic was the U.S. presidents and their impacts on the U.S.
Hours per week:
Advice for students:
Read the chapters. I took this class online and (fatally) didn't take reading the chapters seriously in the first few weeks. Don't kid around. Read them; maybe even take notes. The entire quizzes are based around them, not the lectures.