Most students have seen an exponential model for population growth and know that it predicts unlimited growth. Better models, such as the logistic growth model, should incorporate assumptions to account for limitation of resources. In this activity, participants collect data from a physical simulation of resource-limited growth, prepare a variety of graphs to visualize the data, construct a verbal model based on their observations and the graphs, and (for those who want to go this far) construct a symbolic model from the verbal model.