Horrible, boring books by Hemingway, Faulkner, Fitzgerald, Steinbeck, Maugham, etc. It really turned me off of reading. I hated going to English class because of it.
I wanted to read sci-fi and adventure books, but my teachers said no. In my senior year of high school, I rebelled and refused to do book reports. Getting zeros instead of F's didn't do my GPA any good.
But it's now a long forgotten nightmare and I've been reading my sci-fi and adventure books for many a decade now.