3. Math 55a: Honors Abstract Algebra – This course has been referred to as “the most difficult undergraduate math course in America.” Something to note is that at Harvard, multiple part courses that are intended to be taken in sequence are numbered with letters following the course number. For instance, Math 55a indicates the first semester, whereas Math 55b indicates the second semester. Taught Professor Noam D. Elkies one student writes, “Take his class if you dare!” According to a review in the Harvard Crimson, problem sets can require 25-60 hours a week.
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