Learning to create and use models of real-world situations is an important goal for under-graduate engineers. Engineers today use computer models to explore design problems and test solutions before actually building anything. Learning to create and use models of real-world sit-uations is a challenging task. Most efforts to teach modeling are essentially a means of teach-ing students programming, which is recognized as difficult. In the approach described in this paper, we sought to simplify the task as much as possible away from programming, while still requiring students to learn to use the mathematical models necessary to understand a given sit-uation. We worked in the domain of Chemical Engineering with a tool called DEVICE (Dynamic Environment for Visualization in Chemical Engineering). What we found through an iterative development effort is that emphasizing connections between the real world and the mathematical model led to learning and transfer benefits.