When writer Marcia Segelstein headed to the bookstore to scout out books for her 12-year-old, she wasn’t sure what to expect. But she certainly didn’t expect rampant drinking, drug use, profanity, and explicit descriptions of sex and nudity. Nevertheless, that’s exactly what she found. Segelstein’s daughter had been clamoring to read the Gossip Girl series, which “‘all’ of her friends were reading,” she said. After seeing what was in the books, Segelstein was floored. But a school librarian confirmed, “They’re very popular among sixth and seventh graders.” Even worse, the librarian added, “Some parents are so happy that their kids...