About the Assessment: Participation Rates

National participation

To ensure unbiased samples, NAEP requires that participation rates for original school samples be 70 percent or higher to report national results separately for public and private schools. In instances where participation rates meet the 70 percent criteria but fall below 85 percent, a nonresponse bias analysis is conducted to determine if the responding school sample is not representative of the population, thereby introducing the potential for nonresponse bias.

Before substituting new schools for originally sampled schools that declined to participate, the weighted national school participation rates for the 2009 mathematics assessment were 97 percent for grade 4 (100 percent for public schools and 73 percent for private schools), 97 percent for grade 8 (100 percent for public schools and 72 percent for private schools), and 83 percent for grade 12 (86 percent for public and 52 percent for private). Weighted student participation rates were 95 percent at grade 4, 93 percent at grade 8, and 80 percent at grade 12. The nonresponse bias analysis for private schools at grades 4 and 8 showed that substitution and weight adjustments reduced the potential bias. At grade 12, the school participation rate for private schools fell below the standard for reporting.

Because the grade 12 weighted student participation rate in public schools was below 85 percent (79 percent), a student nonresponse bias analysis was conducted. That analysis showed that the responding student sample differed from the original student sample with respect to race, relative age, and student disability status. After adjusting the sampling weights to account for student nonresponse, the remaining bias was small, with the nonresponse adjusted estimates for the three identified variables differing from the unadjusted estimates by plus or minus 0.1 percentage points.

State and district participation

Standards established by the National Assessment Governing Board require that school participation rates for the original state samples need to be at least 85 percent for results to be reported. In 2009, all 52 states and jurisdictions, along with all 18 districts participating in the mathematics assessment at grades 4 and 8 met this participation rate requirement. Because the weighted school participation rate in Illinois was 84.5 percent, a school nonresponse bias analysis was conducted for the grade 12 public school sample in that state. That analysis showed that the potential nonresponse bias was effectively reduced by including substitute schools and adjusting the sampling weights to account for school nonresponse. The school participation rates for the remaining 10 states all met the required standard with weighted participation rates ranging from 92 to 100 percent.

Student nonresponse bias analyses were conducted at grade 12 for Connecticut, Florida, Illinois, Iowa, Massachusetts, New Hampshire, New Jersey, South Dakota, and West Virginia, where the student response rate fell below 85 percent. Across these nine states, after nonresponse adjustments, the percentage difference between nonresponse adjusted sample and eligible student sample was 1.3 percent or less. Based on the student characteristics available, there does not appear to be evidence of substantial bias resulting from student nonresponse.

The tables below provide participation rates before substitution.

Learn more about the sampling design.

School and student participation rates in NAEP mathematics at grade 4, by state/jurisdiction: 2009
State/jurisdiction	Student- weighted percent	School- weighted percent	Number of schools participating	Student- weighted percent	Number of students assessed
	School participation			Student participation
Nation	97	91	9,510	95	168,800
Public	100	100	8,920	95	163,000
Private	73	68	370	96	2,800
Alabama	100	100	130	98	2,700
Alaska	96	89	160	98	2,600
Arizona	100	100	140	98	3,100
Arkansas	100	100	140	98	2,800
California	100	100	310	98	7,400
Colorado	100	100	150	98	2,700
Connecticut	100	100	130	98	2,700
Delaware	100	100	100	98	2,800
Florida	100	100	180	94	4,700
Georgia	100	100	170	95	4,000
Hawaii	100	100	140	94	2,800
Idaho	100	100	160	96	3,100
Illinois	100	100	230	95	4,100
Indiana	100	100	140	95	2,800
Iowa	100	100	180	95	2,800
Kansas	100	100	150	96	3,000
Kentucky	100	100	190	95	3,800
Louisiana	100	100	150	95	2,900
Maine	100	100	200	93	2,700
Maryland	99	99	200	95	3,400
Massachusetts	97	99	210	94	3,700
Michigan	100	100	190	94	3,400
Minnesota	100	99	170	95	3,300
Mississippi	100	100	130	96	2,900
Missouri	100	100	160	95	2,600
Montana	100	98	240	94	2,700
Nebraska	100	100	170	96	3,000
Nevada	100	100	130	95	3,000
New Hampshire	99	99	160	94	2,700
New Jersey	100	100	140	94	2,900
New Mexico	100	100	160	94	2,800
New York	100	100	180	94	4,100
North Carolina	100	100	190	95	4,400
North Dakota	100	100	250	96	2,000
Ohio	100	100	210	94	3,400
Oklahoma	100	100	180	96	2,900
Oregon	100	100	170	93	2,800
Pennsylvania	100	100	190	95	3,600
Rhode Island	100	100	150	94	2,500
South Carolina	100	100	130	94	2,900
South Dakota	100	100	290	96	2,700
Tennessee	100	100	140	94	2,900
Texas	100	100	270	95	6,300
Utah	100	100	150	95	3,300
Vermont	100	100	220	95	2,700
Virginia	100	100	130	95	2,900
Washington	100	100	160	94	3,200
West Virginia	100	100	190	95	2,800
Wisconsin	99	99	240	95	3,800
Wyoming	100	100	160	94	2,000
Other jurisdictions
BIE¹	88	87	114	92	1,000
District of Columbia	100	100	120	95	1,800
DoDEA²	99	98	110	92	2,000
¹ Bureau of Indian Education. ² Department of Defense Education Activity (overseas and domestic schools). NOTE: The number of schools is rounded to the nearest ten. The number of students is rounded to the nearest hundred. The national totals for schools include Department of Defense Education Activity (overseas and domestic schools) and Bureau of Indian Education schools, which are not included in either the public or private totals. The national totals for students include students in these schools. Columns of percentages have different denominators. 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.