The schools and students participating in NAEP assessments are selected to be representative of all schools nationally and of public schools at the state level. Samples of schools and students are drawn from each state and from the District of Columbia and Department of Defense schools. The results from the assessed students are combined to provide accurate estimates of the overall performance of students in the nation and in individual states and other jurisdictions.
For grade 12, the schools and students participating in NAEP assessments were selected to be representative of all schools nationally and of public schools at the state level in the eleven participating states. There are more public school students selected from the eleven participating states than the non-participating states to provide accurate estimates of the performance of students in those individual states. Proper weighting techniques were applied to insure accurate estimates of the overall performance of students in the nation as well.
While national results reflect the performance of students in both public schools and nonpublic schools (i.e., private schools, Bureau of Indian Education schools, and Department of Defense schools), state-level results reflect the performance of public school students only. Results are also reported separately for Department of Defense schools in state tables and maps. More information on sampling can be found in NAEP Technical Documentation.
The sample of students in the participating Trial Urban District Assessment (TUDA) school districts is an extension of the sample of students who would usually be selected by NAEP as part of state and national samples. Results for students in the TUDA samples are also included in state and national samples with appropriate weighting.
Grade 12 students were not assessed at the district level.
Learn more about the sampling design.