Today, hooking up instead of dating has become the norm.
About two-thirds of teens say at least some of their friends have hooked up.
Experts say today's busier, less attentive parents and the constant displays of casual sex on TV and in the movies have contributed to the change in teen sexual behavior.
"I think young people are getting the message earlier and earlier that this is what everyone is doing," says Stephen Wallace, chairman and CEO of Students Against Destructive Decisions.
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