Though my son is only 2, I do a lot of work with teenagers on a daily basis. There is a blog that I reference often that has incredible information... ESPECIALLY on the topics of dating and sex. It's titled Leading in the Margins.
There is a series titled Let's Talk About Sex and one titled Let's Talk About Dating. They both explain to adults the reasons teens act/think they way they do and give practical advice with practical explanations on why teenagers should or shouldn't do certain things. I've found that it is much easier to teach a teenager something when you can answer their "why?" with more than, "because I said so!"
There is also a lot of information for parents on how to talk to their kids about sex and why it is so important.
Great resource! Highly recommend it!!!!!!