It may not have the gee-whiz factor of high-tech innovation, but changing expectations for what happens in class may prove to be a bigger advance in teaching. In this article, the author discusses a teaching technique called "flipping" and describes how "flipping" the classroom can improve the traditional lecture. As its name suggests, flipping describes the inversion of expectations in the traditional college lecture. It takes many forms, including interactive engagement, just-in-time teaching (in which students respond to Web-based questions before class, and the professor uses this feedback to inform his or her teaching), and peer instruction. The immediacy of teaching in this way enables students' misconceptions to be corrected well before they emerge on a midterm or final exam. The result, according to a growing body of research, is more learning. While the idea is not new, the topic of flipping has consistently cropped up during discussions at recent conferences about teaching and learning--and often when the subject turns to science, technology, engineering, and mathematics, or the STEM disciplines.