A retrospective look at Judy Blume's Forever, a book about a couple's first love and decision to have sex. (The article was published 4 years ago, but is making the rounds again through reproductive health blogs.)
What the article does not mention is the issue of sex outside of romantic relationships which has become more normative in the past decade or two. What I like the most about this book is that having such a healthy relationship of communication portrayed in the book creates an ideal that might discourage teens from pre-relationship and non-monogamous sex. Adolescents have famously short time horizons, and will wait for marriage only extremely particular conditions and maybe not even then, but waiting for a devoted and loving girlfriend or boyfriend rather than just a sex partner may be attainable.