The Common Core State Standards (CCSS) was originally promoted in 2010 by a centrist bi-partisan coalition that included Democrats interested in leveraging more rigorous academic standards to improve educational opportunity and moderate probusiness Republicans concerned about workforce development. As states moved to implement the new Standards (and aligned assessments), an anti-Common Core coalition arose first on the far right among Tea Party activists and then from the left, particularly among teacher advocacy groups. While temporarily united by their opposition to the CCSS, opponents across the political spectrum did not agree on the sources of their concern or on policy solutions. Understanding where the disparate sides of this coalition agreed and disagreed on the specific issue of the Common Core, and education policy more generally, can shed light on the conditions under which transpartisanship might flourish and the extent to which these types of coalitions can impact policy and remain aligned over time. This report examines the controversy surrounding implementation of the CCSS, which offers a case study of a better understanding of the political dynamics and potential limitations of transpartisan coalitions.