Statistics favor a mixed approach at sexual education. Teaching kids about safe sex practices and the consequences of sex reduces pregnancy and disease rates.
Abstinence-only education has been shown to have a negligible effect on sexual activity, and actually increase pregnancy rates in some cases.
Should 15 year-olds be having sex? No. But they're going to. Telling them that condoms are a sin is just hurting them more. Worse, some of the abstinence programs are lying to kids about the effectiveness of condoms for preventing HIV or pregnancy.
If abstinence-only is going to be even attempted, it needs to be reworked because what we have now is broken.
edit - can't type today at all.