The Inside-Out Prison Exchange Program is an international network of teachers and learners who work to break down walls of division by facilitating dialogue across social differences. In this model, first developed by Lori Pompa at Temple University, campus-based college students (outside students) join incarcerated students (inside students) for a college course that is taught inside a correctional facility. Compared to other disciplines, STEM courses are underrepresented in the Inside-Out program. Here we discuss the unique opportunities of teaching a STEM course inside prison using the Inside-Out approach and how it differs from other models of STEM teaching in prison. Our analysis is based on the experience of three instructors from two liberal arts colleges, who taught Inside-Out courses in statistics, number theory, and biochemistry inside a medium-security state prison for men.