One of the hardest classes is Math 55. Math 55 is often regarded as being the hardest undergraduate math class in America. It is a 1 year long course consisting of Math 55a and Math 55b typically taken by freshmen. The course is highly abstract pure math. Interestingly, a very high proportion of the class receive As but this may be a function of the self selection whereby only extremely talented math students take the class. In an average week the class alone can take 20-50 hours. For many the class is the equivalent of a full time job!