Common narratives about teens and social media focus on negative effects on mental health, but there is much more depth and richness in their online lives than meets the eye. Teens are participating in massive online communities with users of all ages from around the world on platforms like Discord, Reddit, and Twitch. Many of these spaces are moderated by teens themselves, and many social media platforms arguably could not exist without them. Who are these teen mods, and what do they do? What are their communities like, and how can we support them? In this talk, I'll share what we've learned about teen mods through our 16 research interviews, as well as what we can do to learn more from them.