In 2010-11, the Mathematics Design Collaborative (MDC) was piloted in four districts and two networks of schools. In most cases, school districts applied for and received grants to implement MDC; in others, national networks were the grantee and the organizer. It is important to note that during the MDC pilot year, the use of FALs was limited in most sites. Many districts received the beta versions of the FALs towards the end of the school year and teachers did not have the opportunity to use them, as they were preparing students for state tests and end-of-course exams. Most teachers have only used the FALs as part of PD sessions. In this report, which draws largely on data from three school districts and one school network, Research for Action (RFA) identifies the conditions and contexts for successful use of the tools, and examines the actions that district and school-based leaders can take to support teachers’ adoption and effective implementation of the math tools. It provides specific recommendations to guide local leaders as they gear up to help year one teachers deepen their use of the MDC tools and teachers who are just joining the initiative to efficiently gain the expertise and skills they need to successfully implement the tools.