This glimpse into sex education in the Los Angeles region illustrates the eugenic ideas about racially “fit” reproduction that emerged in family life curricula during the Second World War. Ideas about eugenic reproduction in public schools responded to broader cultural fears about increasing divorce rates, criminality, immigration, and birthright citizenship. Eugenics in sex and family life education, importantly, portrayed a woman’s choice of mate as a civic responsibility, a move that paved the way for future conflicts about teaching gender and sexuality in public school sex education. Amid a half-century-long conflict over abstinence-only versus comprehensive sex education in public schools, topics like genetics and heredity have come to be widely accepted by both sides—recognized as a presumably value-neutral staple of sex education in US public schools. Yet recent innovations in genetic and reproductive technologies, as well as the conflict over trans and queer youth in the United States, challenge the assumption that teaching genetics and heredity in public schools really is “value neutral.”