This might be old fashioned, but perhaps set the expectation that you do not want your son or daughter dating until they are sixteen. The reality is you can pretend that your teens are not going to have sex, but the earlier they start dating, the sooner that is going to open them up to the world of experimentation and peer pressure to fit in by having sex. Of course I think younger teens can hang out in groups with boys and girls, but there is really little need for younger teens to be dating anyway. As a parent you should be close to your kids and think of activities that will keep their minds on other things than dating. High school is a time when kids should be thinking of academics and their future plans for college, which will be a time when they are old enough to date because they will be on their own, and have more life experience at that time.