The adoption of the Common Core State Standards by 46 states and the District of Columbia represents a dramatic departure in U.S. education. In the past, national efforts to improve education have been directed by the federal government and have emphasized resources or organizational structure. In contrast, the Common Core State Standards in math and language arts were developed under the leadership of state governments to improve the "content" of instruction. A tremendous commitment of time, money, and human resources has gone into creating the new standards--and even more will go into implementing them. If the ambitions of the Common Core initiative are realized, for the first time almost every public school student in the United States will be exposed to roughly the same content, especially in grades 1-8. All of which raises the question, Is all this effort worth it? In the case of mathematics, the authors think the answer is yes because the new math standards will address two long-standing problems in U.S. education: the mediocre quality of mathematics learning and unequal opportunity in U.S. schools. In short, the Common Core State Standards have the potential to improve both quality and equality in mathematics education. (Contains 1 endnote.)