Under the Elementary and Secondary Education Act, states developed their own assessments and set their own proficiency standards to measure student achievement. This has resulted in a great deal of variation among the states, creating a challenge in understanding the ability levels of students across the United States because there is no means to compare one state against the others directly.

To address this need, the National Center for Education Statistics has published periodic reports using the National Assessment of Educational Progress (NAEP) as a common metric for examining the proficiency standards set by states.

This report, prepared by AIR for the U.S. Department of Education, maps state proficiency standards onto the NAEP scales by using state public school data for the 2012–13 school year and the 2013 NAEP assessments. The key finding is that the variation among state achievement standards continues to be wide.