This case study explores a novel form of classroom simulation that differs from published examples in two important respects. First, it is ongoing. While most simulations represent a single learning episode embedded within a course, the ongoing simulation is a continuous set of interrelated events and decisions that accompany learning throughout the semester. Second, it is open-ended, so that students are free to experiment with an infinite quantity of strategies and actions. Student data demonstrates how this simulation positively contributes to learning, engagement, and retention. Finally, tools useful in building and managing such a simulation are discussed.