From 2009 onward, federal policy about sex education tended to favor an evidence-based approach. If a sex education program worked, and was supported by rigorous evidence, the federal government would potentially back it. This was true of sex ed programs that taught students about STDs and contraceptives, and abstinence-based programs. As long as there was evidence for it, the program was eligible. In the last year, policy has dictated that the federal funding show a preference for abstinence-only programs. And spoiler alert, the abstinence-only programs don’t work that well.