13. Of Mice and Men by John Steinbeck
While Steinbeck’s book is definitely a classic, it is on the shorter side of things and its characters are absolutely compelling. The no frills, frugal style and cold-blooded telling of the conditions, the crime, and the aftermath make for an ethically challenging story as well as a literary one. Besides, Of Mice and Men comes up on the AP test all the time, so they may as well get it under their belt.