The Sea Wasp (Ryk E. Spoor)

What you describe is what I had during the school year--required reading for literature class. We'd all study the same book/play/short story and it would be the topic of lessons and discussion.

We also had summer reading lists--that is, at the end of the year or possibly during the summer, we'd be given a list of books that we were supposed to read some number of before next school year started.