As instructors we expect our students to understand what the numbers they generate “mean”. We expect them to be able to visualize, in real or virtual terms, some physical approximation of the “things” they are working with. This visualization provides the basis for a “logic check” on their calculations.Our profession is founded on our ability to specify, within imposed constraints, the physical and functional characteristics of a system that will provide a safe, affordable solution to a problem. Students need to develop and refine this capacity during their undergraduate education. As simple as that may seem to those of us who have experienced the realities of our particular areas of expertise, it is not intuitive. Virtually all academic engineers lament the fact that students regularly submit answers that make no physical sense. The twin questions this issue raises are:1. why do so many students seem to lack an understanding of what their computer generated numbers mean?, and2. how can we help them gain the understanding we want them to have?