Create a safe space for sharing insecurities and feelings. A pair together can share the good they see in the other. Individually, they can list positive traits in a journal.
It depends if you have a teen boy or a teen girl. For a teen girl I think being a part of some kind of social group would be a great idea, an example is cheerleading. For boys the same an example is a sports team.
You may try to encourage groups to go sing karaoke. This active is great as it gives confidence to individuals to sing in front of others. This will help individuals feel good when giving a speech in public.
