A frequent target of censors for its frank depiction of teenage sex and sexuality, Forever was ahead of its time when it was published in 1975. Today, the best-selling novel remains a seminal text about falling in and out of love for the first time—and the experiences that often accompany those milestones. The book is narrated by 17-year-old Katherine Danziger, a New Jersey high schooler who becomes romantically involved with fellow senior Michael Wagner after the two meet at a New Year’s Eve party. Forever traces the progression of Katherine and Michael’s relationship as they develop feelings for one another, become physically intimate and eventually have sex—a decision that prompts some candid conversations about birth control and a visit to Planned Parenthood. In framing Katherine’s internal debate over when to lose her virginity as a personal choice based on emotional readiness rather than a moral dilemma, Judy Blume, a defining author of YA literature, established Forever as a trailblazing novel that has continued to resonate with young-adult readers for nearly half a century. —Megan McCluskey

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