By the end of the first decade of the 21st century, it was clear that nanotechnology was emerging as one of the most promising and rapidly expanding fields of research and development worldwide. It would not be long before scientists, science educators, engineers, and policy makers began advocating for nanoscience, engineering, and technology (NSET) related concepts to be introduced in K-12 classrooms. Indeed, there has been a surge in the development of pre-college NSET-related education programs over the last decade, as well as millions in funding to support the creation of these programs. In an effort to characterize the state of research to date on pre-college students' and teachers' learning of NSET content knowledge and related practices, we have conducted a systematic review of the peer-reviewed, published research studies to answer the following questions: What NSET content knowledge and practices in a pre-college context have been examined in empirical learning studies? What do these studies tell us about the NSET content knowledge and practices that pre-college students and teachers are learning? Implications and recommendations for future research are also discussed.