The Last Picture Show by Larry McMurtry. And also watched the movie?
This is one of McMurtry's most memorable novels - the basis for the film of the same name. Set in a small, dusty Texas town, it introduces Jacy, Duane and Sonny, teenagers stumbling towards adulthood, discovering the beguiling mysteries of sex and the even more baffling mysteries of love.
Also...Summer of '42 Book and Movie. Another young coming of age type book/movie
Teenage Herman Raucher (Gary Grimes), summering on Nantucket Island with his sex-obsessed pals Oscy (Jerry Houser) and Benji (Oliver Conant) during World War II, meets Dorothy (Jennifer O'Neill), a newlywed in her 20s whose husband is off at war. As his friends awkwardly attempt to woo girls their own age, Herman slowly befriends the older woman and finds himself becoming increasingly in love with her, until a sudden tragedy changes their lives forever.