Chemistry is a difficult subject for students to understand because its core concepts--atoms, molecules, and chemical bonds--cannot be directly observed. Students primarily learn chemistry through their senses and do not distinguish between explanations at different conceptual levels. In order to master chemistry, students must develop an understanding of the subject at three different levels: macroscopic, particle, and symbolic (Gabel 1999). This article presents an activity wherein modeling clay is used as an instructional tool to guide students through the three levels of understanding chemistry. The modeling activity is a representative lesson on chemical reactions based on the 5E learning cycle: (1) Engage; (2) Explore; (3) Explain; (4) Elaborate; and (5) Evaluate. The activity leads to the conclusion that models are accessible, affordable, and flexible teaching tools that can enhance student's experiences in chemistry courses. (Contains 4 figures.)