I had a different experience in school, I kept the text book and re-read it. Eventually I had read every text book that I kept (although I did not keep them all) at least once and some of them several times. In my "first" senior year I discovered it was really useful to re-read a text book about a year after I had finished the class, apparently a lot of stuff had settled out by then and since it wasn't coming at me all new at that point I found it really helped me deepen my understanding of the topic generally.