About the Assessment: Target Population and Sample Size

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.

Student sample sizes and target populations in NAEP mathematics at grade 8, by state/jurisdiction: 2009
State/jurisdiction	Sample size	Target population
Nation	167,300	3,849,000
Public	161,700	3,504,000
Private	3,100	337,000
Alabama	2,800	53,000
Alaska	2,500	9,000
Arizona	3,000	73,000
Arkansas	2,600	33,000
California	7,300	469,000
Colorado	2,800	54,000
Connecticut	2,800	42,000
Delaware	2,800	9,000
Florida	4,500	180,000
Georgia	3,600	109,000
Hawaii	2,900	12,000
Idaho	3,000	20,000
Illinois	4,300	154,000
Indiana	2,800	77,000
Iowa	2,700	33,000
Kansas	2,800	33,000
Kentucky	3,800	47,000
Louisiana	2,600	45,000
Maine	2,700	14,000
Maryland	3,500	58,000
Massachusetts	3,800	72,000
Michigan	3,500	117,000
Minnesota	3,000	60,000
Mississippi	2,900	37,000
Missouri	2,700	64,000
Montana	2,700	11,000
Nebraska	2,800	20,000
Nevada	2,900	32,000
New Hampshire	2,600	15,000
New Jersey	2,900	100,000
New Mexico	2,600	23,000
New York	3,900	198,000
North Carolina	4,500	112,000
North Dakota	2,300	7,000
Ohio	3,800	129,000
Oklahoma	2,800	44,000
Oregon	2,900	42,000
Pennsylvania	3,700	127,000
Rhode Island	2,800	11,000
South Carolina	2,900	50,000
South Dakota	2,900	9,000
Tennessee	3,000	75,000
Texas	6,100	322,000
Utah	3,000	38,000
Vermont	2,900	7,000
Virginia	2,900	90,000
Washington	2,900	75,000
West Virginia	3,000	23,000
Wisconsin	3,600	61,000
Wyoming	1,900	6,000
Other jurisdictions
BIE¹	800	2,000
District of Columbia	1,800	4,000
DoDEA²	1,600	5,000
¹ Bureau of Indian Education. ² Department of Defense Education Activity (overseas and domestic schools). NOTE: The sample size is rounded to the nearest hundred. The target population is rounded to the nearest thousand. Data for BIE and DoDEA schools are counted in the overall nation total, but not in the nation (public) total. Data for the District of Columbia public schools are counted, along with the states, in nation (public). Detail may not sum to totals because of rounding. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2009 Mathematics Assessment.

Learn more about the sampling design.