Simple text and black-and-white photographs emphasize the many similarities while explaining the biological differences between the sexes; the photographs show both children and adults and explain matter-of-factly: "If you are a girl, you will grow up to be a woman. Every woman has a vulva and a vagina. . .If you are a boy, you will grow up to be a man. Every man has a penis and testicles." While some adults and children will be uncomfortable with the full frontal nudity in a small proportion of the photos here, this will be useful for those looking for a low-key, nonthreatening, yet graphic explanation of sexual differences to use with young children.