Gosh, that's a great question. I can't wait to see how other people respond. I can't think of anything that was too horrible. In junior college I took an easy summer class in ecology. One day we had to read a leftist article that blasted the rich western countries for polluting the earth, and we were asked to write an essay on the article. Since I had been to a few third world countries and the college was located in an area that was heavily populated by welfare recipients, I argued that poor people and poor countries polluted the most --welfare people couldn't afford decent running cars, so they always had several junky cars parked around their dried up lawns. Poor countries couldn't afford the environmental laws that would cut emissions. I got an A in that class.
In university, the worst class was probably modern American history. We had to read Backfire,a book that blames American puritanism, in part, for the Vietnam war, and I also had to suffer through a Bill Moyers special that was highly critical of Ronald Reagan.
Bill Moyers- I sat through an entire week of class time watching his "documentary" on Reagan and Iran Contra. Me and another classmate asked enough questions to cause the teacher to send us out of the room and then come us to us personally and ask us not to "disrupt" his class. We were intimidated and then stayed silent. I am ashamed of that to this day.