When passing hot rolls around the dinner table, buying popcorn at a movie theater, or making cookies, it is there: butter. Creating butter in a bottle helps students see how a physical change can be more drastic than an ice cube melting. This experiment provides an opportunity for students to use observation skills to investigate how a liquid heavy cream can undergo a physical change to become butter. This lab also can be used for study of the creation and utilization of calories, and of comparing and contrasting physical and chemical changes.