Samples, Inclusion, and Participation
The schools and students participating in NAEP assessments are selected to be a nationally representative sample of all schools. The results from the 2018 geography assessment at grade 8 are based on approximately 12,900 eighth-graders from 780 schools who took the assessment on paper or tablets. Results for the nation reflect the performance of students attending public schools, private schools, Bureau of Indian Education schools, and Department of Defense schools. Download the summary data tables via the link at the bottom of the page to see the national sample sizes for the 2018 geography assessment.
Each school that participated in the assessment, and each student assessed, represents only a portion of the larger population of interest. The results are weighted to account for the disproportionate representation of some groups in the selected sample, including the oversampling of schools with high concentrations of students from certain racial/ethnic groups and the lower sampling rates of students who attend small schools. Read more about NAEP sampling and weighting in the NAEP Technical Documentation.
NAEP Inclusion
Assessing representative samples of students, including students with disabilities (SD) and English language learners (ELL), helps to ensure that NAEP results accurately reflect the educational performance of all students in the target population and are a meaningful measure of U.S. students’ academic achievement over time.
To ensure that all selected students from the population can be assessed, many of the same accommodations that SD and ELL students use on other tests are provided for those students participating in NAEP. Accommodations were first made available for the geography assessment in 2001. Read more about accommodations available in NAEP. In the 2018 NAEP digitally based geography assessment, accommodations such as text-to-speech for directions were universal design elements integrated into the delivery system and available to all students.
Because providing accommodations represented a change in testing conditions that could potentially affect the measurement of changes over time, split national samples of students were assessed in 2001—one sample permitted accommodations and the other did not. Although the results for both samples are presented in the tables and figures, any comparisons to 2001 in the text are based only on the accommodated sample.
The National Assessment Governing Board, which sets policy for NAEP, has been exploring ways to ensure that NAEP continues to appropriately include as many students as possible and to do so in a consistent manner for all jurisdictions and districts assessed and reported. In March 2010, the Governing Board adopted a new policy outlining specific inclusion goals for NAEP samples. The goal is to include 95 percent of all students selected for the NAEP samples, and 85 percent of those in the NAEP sample who are identified as SD or ELL. Read more about the inclusion policy and how the percentages of students are calculated.
School and Student 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 replacing originally sampled schools that declined to participate with substitute schools, the weighted national school participation rates for the 2018 geography assessment were 82 percent for grade 8 (84 percent for public schools, 49 percent for private schools, and 86 percent for Catholic schools). In 2018, the school participation rates for private schools at grade 8 did not meet the criteria so their results are not reportable.
Weighted student participation rates were 92 percent at grade 8 (92 percent for public school students, 93 percent for private school students, and 94 percent for Catholic school students).
Download the summary data tables via the link at the bottom of the page to see the participation rates in geography for the nation.
About the NAEP Geography Assessment
The National Assessment of Educational Progress (NAEP) in geography is designed to measure students' knowledge, understanding, and application of geography in the content areas of Space and Place, Environment and Society, and Spatial Dynamics and Connections. Students answer a series of selected-response and open-ended questions based on these content areas in geography. Performance results are reported for students in the nation and disaggregated by various student characteristics.
In 2018, the NAEP geography assessment transitioned from a paper-based assessment (PBA) to a digitally based assessment (DBA) at grade 8. A multi-step process was used for the transition from PBA to DBA, which involved administering the assessment in both formats to randomly equivalent groups of students in 2018. The transition was designed and implemented with careful intent to preserve trend lines that show student performance over time. Thus, the results from the 2018 geography assessment can be compared to results from previous years.