When I was in college, we had a particularly difficult Discrete Math professor. It was easily the most difficult course by a long shot in my entire schooling. Many of us dropped the class halfway through the first time around since our grades had no hope of recovering by semester's end. A good number of people would then go take the course at a local community college and transfer the credits in. I was not so ambitious, and put the class off until the final semester of my senior year. Luckily, they had added another professor, and his course, while covering the same subjects, was a breeze.