This document discusses teens' digital lives and the changing world they will encounter. It notes that while teens today are constantly connected through social media on personal devices, they still need guidance and support to develop critical thinking skills. New technologies like 3D printing will continue disrupting industries. The document examines how teens' brains develop differently than in the past and how they learn in multiple ways. It stresses the need for libraries to support 21st century learning and engage teens across different platforms and experiences.