how many states have adopted common core standards
State Adoption of the Common Core State Standards: the 15 Percent Rule 5 C OMMON C ORE S TATES THAT A DDED C ONTENT U NDER THE 15 P ERCENT R ULE Of the 46 entities that have adopted the Common Core State Standards, 11 states elected to add new state-specific content in at least one subject area.