The education initiative known as Common Core was initially adopted, in some states, as early as 2010, with Kentucky being the first state. Originally, 46 states passed laws adopting the Common Core standards in their schools.
Despite this almost universal ratification of the Common Core initiative, implementation has been challenging, and even though many states have adopted it, through funding or protest issues, many have not yet been able to implement it into their schools.
The four states that never adopted the Standards are Virginia, Texas, Alaska, and Nebraska. The four states who have successfully withdrawn from the curriculum are Arizona, Oklahoma, Indiana, and South Carolina. These eight states are typically republican-controlled, implying there is some correlation between political party affiliation and rejection of common core.
While still technically adopted as the official curriculum, at least 16 states have begun or passed legislation to repeal the standards. Besides the four states listed above, 12 states are in the process of repealing Common Core.
These states, not shown on the map below are Alabama, Colorado, Florida, Georgia, Kansas, New Hampshire, North Carolina, Ohio, Pennsylvania, Tennessee, West Virginia, and Maryland. Assessing involvement and support for Common Core is extremely difficult because the newest data and mapping available is from 2014.
Furthermore, many of the states who have “repealed” the standards have adopted their own which are still in accord with the standards, and thus the relationship between the state and Common Core is extremely convoluted. It seems its fate in most states is no longer of interest to most people.
Minnesota was, at least originally, unique in their adoption of the Common Core Standards. They were the only ones to partially adopt it from the start as they used only the English standards and developed their own math standards.
There is no correlation between states that have adopted Common Core and their educational ranking.