this commitment to deep collaboration also requires new types of materials aligned to the standards, with a focus on real-time assessment and its translation into classroom practice. Two examples of this kind of collaboration are the Literacy Design Collaborative (LDC) and the Mathematics Design Collaborative (MDC), through which groups of traditional public school and public charter school teachers, curriculum experts, and other educators are working together to create high-quality, useful lessons and research-based instructional tools incorporating the common-core standards. In addition to developing a free, online library of new lessons and units, these efforts, funded by the Gates Foundation, are pioneering new pathways for how educators can work together to shift teacher practice.