The Common Core State Standards promise to raise expectations for all students by establishing consistent college- and career-ready learning goals across the country. The standards build on the best of the current state standards informed by the experiences of top-performing countries. Most importantly, they focus on what is most essential at each grade level, bringing coherence and focus, rather than asking students and teachers to learn less and less about more and more. Implementation of the Common Core provides an opportunity for states and districts not only to raise expectations, but also to rethink how they support teachers with instructional materials and professional learning. The Common Core will require teachers to shift their instructional practice in significant ways. To build long-term understanding and ownership, training