Sex education is a term used to describe educational classes that are designed to teach individuals - usually school-aged children - about human sexuality and reproduction. Many states require public schools to offer sex education. Although some schools begin age-appropriate sex education as early as elementary school, most students have their first sex education classes while they are in middle school. Some topics covered during sex education include sexual anatomy, puberty, reproduction, sexual health, sexually transmitted diseases, birth control and abstinence. Many school districts are also required to teach students about HIV and AIDS safety.