My daughter had a kissing incident with a boy at school and her pre-K teacher handled by telling them there's no kissing until you get your drivers license.

I had a very clinical talk with her older sister when she was still a pre-teen. It was easy because she grew up around farms and witnessed birth and animal screwing regularly. I gave her lots of info, then added a caveat that she should wait until she's truly in love. I told her that she'd meet some awesome prince-like guy in college and wouldn't it be amazing to have waited? I couldn't imagine not being able to talk to my girls about sex. It's life and death these days.

It's okay to be a hypocrit as a parent. Up until a few years ago, my primary goal in life was to screw as many chicks as possible, with the idea that 'there's nothing like something new' (Trent Reznor).