“Modeling Dynamics Systems: Lessons for a First Course” provides a set of materials that enable educators at the secondary and college levels to teach a one-semester or one-year course in System Dynamics modeling. These lessons are also useful for trainers in a business environment. Developed for beginning modelers, the lessons contained in this book can be used for a core curriculum or for independent study. Systems thinking software like STELLA offers an opportunity to create visual models that actively engage students in the study of a wide variety of problems. Creating a model allows for “real-time” analysis of dynamic behavior and a more stimulating environment in which to glean insight. The lessons include some of the classic System Dynamics problems (population change, resource sustainability, drug pharmacokinetics, spread of an epidemic, urban growth, and more). Developed over 14 years, the lessons in this book provide an easy-to-use set of teaching materials that are paced gently enough for novice modelers. Students learn to create progressively more sophisticated models, testing their structures as they proceed. Feedback analysis is integral to the lessons. Guidelines for an independent project and an outline for a technical paper explaining the creation process, are included.