Integrated STEM (science, technology, engineering, and mathematics) education is becoming increasingly common in K–12 classrooms. However, various definitions of STEM education exist that make it challenging for teachers to know what to implement and how to do so in their classrooms. In this article, we describe a series of activities used in a week-long professional development workshop designed to elicit K–12 teachers’ conceptions of STEM and the roles that science, technology, engineering, and mathematics play in STEM education. These activities not only engage teachers in conversations with peers and colleagues in a professional development setting but also enable teachers to reflect on their learning related to STEM education in the context of creating lesson plans and considering future teaching. In addition to describing these activities, we share suggestions related to how these activities may be used in venues outside of professional development.