Teens choose their friends, because of similar interests, or to make themselves more popular. Their peers influence issues such as style and activities. The focus is on fitting in. Before deciding to do something, teens often ask themselves, "What will my friends think?" This does not mean their decisions are stupid. It means that there is a trade-off between doing what one knows is right, and being accepted by peers. It also means you and your teen may identify different consequences of a behavior and may value those consequences differently.
Missing the coolest party on Saturday night is not a big deal to you, but it seems like the worst thing in the world to your teen.
For you, having unprotected sex might potentially lead to pregnancy or a sexually transmitted infection, while your teen may feel not having sex might mean losing her boyfriend. This doesn't mean you're not important. When parents monitor their teen's behavior, the teen is more likely to choose friends who participate in behaviors parents approve of. Parents need to remain close to their teens and make sure teens balance family time with the time they are spending with peers. Parents with a good relationship with their teen will have more influence than peers