Forty-four states and the District of Columbia have adopted the Common Core State Standards in English language arts and mathematics. Despite initial enthusiasm, criticism of and outright opposition to the standards are beginning to arise. , a senior fellow in the  at Brookings, explains how the Common Core came about, why some are opposed to it now, and what his research shows about its impact on student achievement. Show notes: •  (Loveless)•  (Loveless, in 2012 Brown Center Report)•  (West and Bleiberg)•  (Brown Center event)•  (West and Bleiberg)•  (Brown Center event)•  (Loveless)•