I had good sex-ed books growing up, from what I remember. They were straight-forward, science based and once I got over the obligatory "eww gross!" reaction, they were really quite interesting. This book, however, outshines them all.
Let me get my one complaint out of the way: the subtitle. "The all-you-need-to-know progressive sexuality guide to get you through high school and college" alienates anyone who doesn't finish high school, doesn't plan to go to college, or pursues an alternative education and quite often these are the people who most need access to reliable information about their sexual health. In reading the book, I didn't find the content to reflect this bias which was a relief.
But back to the book itself. The author is the founder and owner of Scarleteen, probably the best web resource for teen sexuality. If anyone knows what teens actually want and need to know about sex and sexuality, she'd be the person. Right from the start she tells us that she won't be spending much time on discussing abstinence, backing that decision up with the following statistic: "…about 26 percent of young adults 'practicing abstinence' will become pregnant within one year." Instead she accepts that most young people will want and eventually have sex and tries to prepare them for that eventuality. Unlike may sex-ed books, she goes beyond just explaining how not to get pregnant or contract an STI - she actually talks about how to have GOOD sex. The discussion of safer sex includes the usual physically safer sex, but also emotionally safer sex.
There's a ton of good stuff in this book, including realistic descriptions of what you will experience in an OB/GYN appointment, how to use the various kinds of birth control (including cost and effectiveness), and what an abortion is actually like without all the scare tactics. There is also a recognition that teens don't always (or often) wait for a long-term relationship in order to have sex; many will have hook ups, one night stands or friends with benefits. Queer, genderqueer, and kinky teens will all find themselves represented here which is refreshing change of pace in the world of sex-ed.
Above all the author stresses communication: if you can't talk to your partner about what you want and need from a sexual encounter, you should probably rethink having sex with them at all. Will this prevent anyone who reads it from having bad sex? Probably not, but the more that message gets out there, the sooner they WILL start demanding what they need in their sexual lives, something that people of all ages will benefit from!