Strong instructional materials are crucial to realizing the promise of the Common Core State Standards. Research suggests that the choice of instructional materials can have an impact as large as or larger than the impact of teacher quality. Unfortunately, many popular textbooks are not aligned to the new standards, leaving educators scrambling. However, tools exist to help educators spot quality and encourage publishers to provide it. States like Louisiana and New York have incorporated these tools into their efforts to develop and identify materials, with several lessons for educators and leaders looking to do the same.