When they run with the crowd that is another story. They are easily led. Group pressure sweeps them along in values they would not otherwise hold. If they get into the right crowd where they can see living, flesh and blood, examples of those who walk with the Lord, the impact will be for good. Paul reminded the Philippians many times of those who would detract from their lives.
Leadership takes responsibility to constantly warn their followers of danger.
Good leadership identifies negative influences and structures countervailing principles into the people they lead. Peer pressure cannot transcend fifteen years of values inculcated into the life. If our teens are secure enough in themselves that they can stand against the crowd, they have reached a maturity beyond most. If we are to build teens who are independent of social pressure, we need to communicate biblical convictions at a young age. We need many young men and women who, like Daniel, dare to stand alone.