The Good Earth was one of my favorites in high school.

Other American Lit I read freshman & junior year in HS that I loved:

High Tide in Tuscon, Kingsolver
Joy Luck Club, Tan
The Chosen, Potok
Ferenheit 451, Bradbury
Huck Finn, Twain
The Red Pony, Steinbeck
Black Boy, Wright
Black Like Me, Griffin
The Scarlet Letter, Hawthorne
The Beet Queen, Erdrich

Plus several of the above. I left off the stuff I hated (Faulkner, Uncle Tom's Cabin)