But protecting kids from life's moral and physical challenges is not good, and can be damaging. Promiscuity is dangerous. We must do everything to keep kids from sexually acting out. This means preventing kids from getting into sexual situations. Let kids know you aren't just paying lip service to chastity.
Parents have no obligation to tell the truth about their own adolescence.
Tell kids that sex can be no more significant than scratching a powerful itch, or an extraordinary blessing in the context of commitment. But commitment requires time and maturity. That's the main reason kids should not have sex. The prohibition against drugs should include alcohol. Infringement should trigger serious consequences, such as grounding or loss of car privileges.