U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics. National Assessment of Educational Progress Assessments (NAEP),2024, 2022, 2019, 2017, 2015, 2013, 2011, 2009, 2007, 2005, 2003 Mathematics Assessments. Accessed through the NAEP Data Explorer, at
http://nces.ed.gov/nationsreportcard/naepdata/.