>>The truth of the matter: better safe than sorry. Birth Control in reality is needed especially by teens (not necessarily encouraged). Just ask Bristol Palin (although I'm sure she has nothing to worry about unlike poor teens who are even more likely to take chances!)
I know of two other options for girls:
1) Equestrian pursuits
2) Competitive gymnastics
Both of these make girls fit and strong while keeping them too busy for anything else including facebooking, sexting or loitering in malls. ;-) Current recommendation is that daughters can safely continue these pursuits until at least age 25. ;-)
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1