Molecular modeling is pervasive in the pharmaceutical industry that employs many of our students from Biology, Chemistry and the interdisciplinary majors. To expose our students to this important aspect of their education we have incorporated a set of tutorials in our Biochemistry class. The present article describes one of our tutorials where undergraduates use modeling experiments to explore the structure of an estrogen receptor. We have employed the Molecular Operating Environment, a powerful molecular visualization software, which can be implemented on a variety of operating platforms. This tutorial reinforces the concepts of ligand binding, hydrophobicity, hydrogen bonding, and the properties of side chains and secondary structure taught in a general biochemistry class utilizing a protein that has importance in human biology.