A project of the National Science Foundation, ChemConnections modules use guided, discovery-based learning activities to promote a deep understanding of a broad range of chemistry concepts and problem-solving techniques. Each module poses a central question for example, "What's in a Star?" or "How Can We Make Our Water Safe to Drink?" that students investigate through guided discussions, collaborative laboratory work, reading and writing assignments, case teaching, policy simulations, Web research, and videos.

Rowland and Molina s two-step chlorine-catalyzed cycle, the unique Antarctic meteorology, and heterogeneous chemistry complete the story of Antarctic ozone depletion. Using chemical kinetics in a real context is emphasized through rate concepts and calculations that answer relevant questions about ozone. Students also learn to support or refute a scientific hypothesis with evidence and to consider the interplay between experimental data and theoretical models."