This article discusses how to use popcorn to engage students in model building and to teach them about the nature of matter. Popping kernels is a simple and effective method to connect the concepts of heat, motion, and volume with the different phases of matter. Before proceeding with the activity the class should discuss the nature of scientific models. The students need to realize that models are (1) imperfect representations of unobservable phenomena and (2) designed by scientists to address specific questions (Gilbert and Ireton 2003). By addressing the limitations of models, the students are able to compare and contrast the model to the natural phenomenon. For example, teachers use models to teach students about the solar system. These models are limited because they are not to scale in terms of the relative sizes of the planets or the distances between the orbits. By discussing the limitations of the model, the students learn the attributes of the solar system and gain a better understanding of scientific models.