Learning in the 21st century means thinking in complex and collaborative ways that are situated in a real world context. David Shaffer will introduce Epistemic Network Analysis (ENA), a tool for modeling complex thinking. A central premise of ENA is that complex thinking is characterized by a network of connections in a domain. Originally designed to assess epistemic frames, collections of skills, knowledge, identities, values, and ways of making decisions„in virtual game environments, ENA is now being used broadly to quantify the structure of connections that constitute complex thinking in large-scale datasets and logfiles of many kinds, including but not limited to chat, email, and actions online.