In this article, the authors discuss three trends that are reshaping our world and the ways we get work done. The authors then discuss the implications of these trends, both for how we educate our young and how we train and develop our teachers. To that end, the authors propose an approach to teacher training and professional development situated entirely in K-12 schools. The authors outline design principles for such an approach. The authors illustrated with examples from the High Tech High Graduate School of Education.