Calculus provides the language and some powerful tools for the study of change. As such, it is an essential subject for those interested in growth and decay processes, motion, and the determination of functional relationships in general. Using student-selected models from primary literature, we will investigate dynamical systems from economics, ecology, epidemiology and physics. Computers are essential tools in the exploration of such processes and will be integral to the course. No previous programming experience is required. Topics will include: 1) dynamical systems, 2) basic concepts of calculus-- rate of change, differentiation, limits, 3) differential equations, 4) computer programming, simulation, and approximation, 5) exponential and circular functions. While the course is self-contained, students are strongly urged to follow it up by taking NS 316-Linear Algebra or NS 261-Calculus II to further develop their facility with the concepts. In addition to regular substantial problem sets, each student will apply the concepts to recently published models of their choosing. This course satisfies Division I distribution requirements.