The well-being of children is an overarching societal goal. Teens ages 13 through 18 are a significant child subgroup, comprising 25.1 million Americans, or 2 out of 5 children. As adolescents, teens live through a critical developmental period, during which their circumstances, brains and bodies are undergoing multiple changes. Many of today’s teens—including and beyond those diagnosed with mental disorders—are not flourishing to the extent they could be. Further, evidence is growing that thriving teens would be able to contribute to the well-being of their families, communities, and the nation.