I hate to post two threads in a row, but I have too many physics questions going in my head to sleep. My TA last semester told us he was taking a QM course and told us his uncurved class average was a 37. This leads me to think that no undergrad can grasp QM. Now I know only the most basic of concepts involving QM, is it that difficult to understand or is it just very difficult to explain? If the class average of 4th year undergrads is 37 that either means the teacher is awful, or the subject matter is just on another level of comprehension.