Not sure if you want something from a Christian perspective, but I recently bought a book called "Love, Sex, and God" (it says it is for ages 14 and up) that covers STDs, anatomy (there are drawings of a male and female, standing, as well as another drawing of the genitals of each) . The book also mentions (briefly) oral and anal sex, transgender issues, dating, marriage, how to know when you are ready to have a baby, etc.