I love teaching Steinbeck's short novel (go ahead, call it a novella) of friendship and dreams during the Great Depression. Students tend to love it, too--at least those who read it.
And at just under 30, 000 words*, most students will give it a try.
Steinbeck's language is beautiful but straight-forward, his dialogue and voice spot on. Of Mice and Men is a great vehicle for teaching characterization, foreshadowing, and theme.
I love this book, and I'm fortunate to have the opportunity to read it every year.
*How would Steinbeck have pitched a 30K novel in today's publishing world? Would he have self-published on Kindle because the big 6 were looking for 100K novels? Sorry--couldn't help myself. But just think of the gap in American literature if Of Mice and Men never saw print.