Charter schools represent an increasingly important form of school choice in the United States. Charter schools are public schools, with a difference. Compared to traditional public schools, they are exempted from some of the state laws and regulations that govern traditional public schools. In this way, parents come to have a greater number of…

In this paper, we describe a model for systematically improving the mathematics preparation of elementary teachers, one lesson at a time. We begin by identifying a serious obstacle for teacher educators: the absence of mechanisms for developing a shareable knowledge base for teacher preparation. We propose our model as a way to address this…