That depends entirely on the class! I had classes that were easy even if I didn't go to class, and others that were hard even if I went to every class. (I even signed up for overlapping courses once, and skipped out of an uninteresting mandatory one halfway through every lecture to go to the other.) Far more important to me was getting together with other students to work on the material.

That's what college is about: figuring out how you learn best. If you know that, your school/major/etc. don't matter.