Overview of the Assessment
Reporting the Assessment—Scale Scores and NAEP Achievement Levels
Description of U.S. History Performance by Item Maps for Each Grade
Results Are Estimates
NAEP Reporting Groups
Cautions in Interpretations
NAEP assesses student performance in U.S. history by administering assessments to samples that are representative of the nation's students. The content of the NAEP U.S. history assessment is determined by a framework developed with the help of researchers, policymakers, and the interested public, including those with expert perspectives about U.S. history and its measurement. Read more about what the assessment measures, how it was developed, who took the assessment, and how the assessment was administered.
The 2018 U.S. history results presented on the website are based on a representative sample of eighth-grade students in the nation. Approximately 16,400 eighth-graders from 780 schools participated in the assessment. The national results reflect the performance of students attending both public and nonpublic schools. Results from 2018 are compared to results from the previous U.S. history assessments administered in 1994, 2001, 2006, 2010, and 2014. In 1994, students were not offered accommodations as part of the NAEP assessments; however, in 2001, NAEP administered the assessment with both a sample who were allowed accommodations and those who were not allowed accommodations. Changes in student performance across years or differences between groups of students in 2018 are discussed only if they have been determined to be statistically significant.
The results of student performance on the NAEP U.S. history assessment are presented on this website in two ways: as average scores on the NAEP U.S. history scale and as the percentages of students attaining NAEP U.S. history achievement levels. The average scale scores represent how students performed on the assessment. The NAEP achievement levels represent how that performance measured up against set expectations for achievement. Thus, the average scale scores represent what students know and can do, while the NAEP achievement-level results indicate the degree to which student performance meets expectations of what they should know and be able to do. In addition to reporting an overall U.S. history score for each grade, scale scores are reported at five percentiles to show trends in results for students performing at lower (10th and 25th percentiles), middle (50th percentile), and higher (75th and 90th percentile) levels.
Average U.S. history scale score results are based on the NAEP U.S. history scale, which ranges from 0 to 500. The NAEP U.S. history assessment scale is a composite combining separate scales for each of the four U.S. history themes specified by the U.S. history framework. Average scale scores are computed for groups of students; NAEP does not produce individual student scores. The average scores are based on analyses of the percentages of students who answered each item successfully.
NAEP achievement levels are performance standards that describe what students should know and be able to do. Results are reported as percentages of students performing at or above three achievement levels (NAEP Basic, NAEP Proficient, and NAEP Advanced). Students performing at or above the NAEP Proficient level on NAEP assessments demonstrate solid academic performance and competency over challenging subject matter. It should be noted that the NAEP Proficient achievement level does not represent grade-level proficiency as determined by other assessment standards (e.g., state or district assessments). NAEP achievement levels are to be used on a trial basis and should be interpreted with caution. See more information about NAEP U.S. history achievement levels.
Because NAEP scores and achievement levels are developed independently for each subject, results cannot be compared across subjects.
Item maps illustrate the knowledge and skills demonstrated by students performing at different scale points on the NAEP U.S. history assessments. In order to provide additional context, the cut points for the three NAEP achievement levels are marked on the item map. The map location for each question represents the scale score attained by students who had a 65 percent probability of obtaining credit at a specific level of constructed-response questions or selected-response questions that don't involve a guessing factor, a 74 percent probability of correctly answering a four-option multiple-choice question, or a 72 percent probability of correctly answering a five-option multiple-choice question in certain subjects. For constructed-response questions, responses may be completely or partially correct; therefore, different types of responses to the same question could map onto the scale at different score levels.
Approximately 20 to 30 U.S. history questions from the 2018 assessment have been selected and placed on an item map for grade 8. No new items were released from the 2018 U.S. history assessment.
The average scores and percentages presented on this website are estimates because they are based on representative samples of students rather than on the entire population of students. Moreover, the collection of subject-area questions used at each grade level is but a sample of the many questions that could have been asked. As such, NAEP results are subject to a measure of uncertainty, reflected in the standard error of the estimates. The standard errors for the estimated scale scores and percentages in the figures and tables presented on this website are available through the NAEP Data Explorer.
Results are provided for groups of students defined by shared characteristics—race/ethnicity, gender, eligibility for free/reduced-price school lunch, highest level of parental education, type of school, charter school, type of school location, region of the country, status as students with disabilities, and status as students identified as English language learners. Based on participation rate criteria, results are reported for various student populations only when sufficient numbers of students and adequate school representation are present. The minimum requirement is at least 62 students in a particular group from at least five primary sampling units (PSUs). However, the data for all students, regardless of whether their group was reported separately, were included in computing overall results. Explanations of the reporting groups are presented below.
Prior to 2011, student race/ethnicity was obtained from school records and reported for the six mutually exclusive categories shown below:
Students who identified with more than one of the other five categories were classified as “other” and were included as part of the "unclassified" category along with students who had a background other than the ones listed or whose race/ethnicity could not be determined.
In compliance with new standards from the U.S. Office of Management and Budget for collecting and reporting data on race/ethnicity, additional information was collected beginning in 2011 so that results could be reported separately for Asian students, Native Hawaiian/Other Pacific Islander students, and students identifying with two or more races. Beginning in 2011, all of the students participating in NAEP were identified by school reports as one of the seven racial/ethnic categories listed below:
Students identified as Hispanic were classified as Hispanic in 2011 and subsequent years even if they were also identified with another racial/ethnic group. Students who identified with two or more of the other racial/ethnic groups (e.g., White and Black) would have been classified as “other” and reported as part of the "unclassified" category prior to 2011, and classified as “Two or More Races” from 2011 on.
When comparing the results for racial/ethnic groups from 2014 and 2018 to earlier assessment years, the data for Asian and Native Hawaiian/Other Pacific Islander students were combined into a single Asian/Pacific Islander category. Information based on student self-reported race/ethnicity will continue to be reported in the NAEP Data Explorer.
Results are reported separately for males and females.
As part of the Department of Agriculture's National School Lunch Program (NSLP), schools can receive cash subsidies and donated commodities in turn for offering free or reduced-price lunches to eligible children. Based on available school records, students were classified as either currently eligible for the free/reduced-price school lunch or not eligible. Eligibility for free and reduced-price lunches is determined by students' family income in relation to the federally established poverty level. Students whose family income is at or below 130 percent of the poverty level qualify to receive free lunch, and students whose family income is between 130 percent and 185 percent of the poverty level qualify to receive reduced-price lunch. For the period July 1, 2017 through June 30, 2018, for a family of four, 130 percent of the poverty level was $31,980 and 185 percent was $45,510. The classification applies only to the school year when the assessment was administered (i.e., the 2017–18 school year) and is not based on eligibility in previous years. If school records were not available, the student was classified as "Information not available." If the school did not participate in the program, all students in that school were classified as "Information not available." Because of the improved quality of the data on students' eligibility for NSLP, the percentage of students for whom information was not available has decreased compared to the percentages reported prior to the 2003 assessment. As a result of the passage of the Healthy, Hunger-Free Kids Act of 2010, schools can use a new universal meal service option, the "Community Eligibility Provision" (CEP). Through CEP, eligible schools can provide meal service to all students at no charge, regardless of economic status and without the need to collect eligibility data through household applications. CEP became available nationwide in the 2014-2015 school year; as a result, the percentage of students in many states categorized as eligible for NSLP may have increased in comparison to 2013 due to this provision. Therefore, readers should interpret NSLP trend results with caution. See the proportion of students in each category in the NAEP Data Explorer.
Parents' highest level of education is defined by the highest level reported by eighth-graders for either parent. Parental education attainment is one component used to measure student's socioeconomic status (SES).
The national results are based on a representative sample of students in both public schools and nonpublic schools. Nonpublic schools include private schools, Bureau of Indian Affairs schools, and Department of Defense schools. Private schools include Catholic, Conservative Christian, Lutheran, and other private schools. The sample sizes for BIE, Department of Defense schools, and other private schools are often too small to permit reliable estimates. Please visit the NAEP Data Explorer for more details about the results for type of school categories. The participation rate for private schools at grade 8 did not meet the NAEP reporting standards in 2018; therefore, their results are not shown in the "type of school" charts in hte 2018 U.S. history report.
A pilot study of America's charter schools and their students was conducted as part of the 2003 NAEP assessments in reading and mathematics at grade 4. Results are available for charter schools starting in 2003 or later assessment years at grade 4, in 2005 or later assessment years at grade 8, and in 2009 or later assessment years at grade 12. Results for this variable are presented for public school students in the NAEP reports.
NAEP results are reported for four mutually exclusive categories of school location: city, suburb, town, and rural. The categories are based on standard definitions established by the Federal Office of Management and Budget using population and geographic information from the U.S. Census Bureau. Schools are assigned to these categories in the NCES Common Core of Data based on their physical address. In 2007, the classification system was revised; therefore, results for school location are available for 2007 and later assessment years.
In 2007, the classification system was revised; therefore, trend comparisons to previous years are not available. The new locale codes are based on an address's proximity to an urbanized area (a densely settled core with densely settled surrounding areas). This is a change from the original system based on metropolitan statistical areas. To distinguish the two systems, the new system is referred to as "urban-centric locale codes." The urban-centric locale code system classifies territory into four major types: city, suburban, town, and rural. Each type has three subcategories. For city and suburb, these are gradations of size—large, midsize, and small. Towns and rural areas are further distinguished by their distance from an urbanized area. They can be characterized as fringe, distant, or remote.
Prior to 2003, NAEP results were reported for four NAEP-defined regions of the nation: Northeast, Southeast, Central, and West. As of 2003, to align NAEP with other federal data collections, NAEP analysis and reports have used the U.S. Census Bureau's definition of "region." The four regions defined by the U.S. Census Bureau are Northeast, South, Midwest, and West. The Central region used by NAEP before 2003 contained the same states as the Midwest region defined by the U.S. Census. The former Southeast region consisted of the states in the Census-defined South minus Delaware, the District of Columbia, Maryland, Oklahoma, Texas, and the section of Virginia in the District of Columbia metropolitan area. The former West region consisted of Oklahoma, Texas, and the states in the Census-defined West. The former Northeast region consisted of the states in the Census-defined Northeast plus Delaware, the District of Columbia, Maryland, and the section of Virginia in the District of Columbia metropolitan area. The table below shows how states are subdivided into these Census regions. All 50 states and the District of Columbia are listed. Other jurisdictions, including the Department of Defense Educational Activity schools, are not assigned to any region.
Results are reported for students who were identified by school records as having a disability. A student with a disability may need specially designed instruction to meet his or her learning goals. A student with a disability will usually have an Individualized Education Program (IEP) which guides his or her special education instruction. Students with disabilities are often referred to as special education students and may be classified by their school as learning disabled (LD) or emotionally disturbed (ED).
Most figures in the U.S. history web results show two data points in 2001—one in which accommodations were permitted and one in which they were not. While results for both 2001 samples are presented, comparisons between 2001 and 2014 are based on the accommodated samples of both years. When results for students with disabilities are presented, only the accommodated sample data are shown. Accommodations were not offered prior to 2001.
Results are reported for students who were identified by school records as being English language learners. When results are presented for English language learners, only the accommodated sample is presented as the 2001 starting point in the trend line. (Note that English language learners were previously referred to as limited English proficient [LEP].)
NAEP has established policies and procedures to maximize the inclusion of all students in the assessment. Every effort is made to ensure that all selected students who are capable of participating meaningfully in the assessment are assessed. While some students with disabilities (SD) and/or English language learners (ELL) can be assessed without any special procedures, others require accommodations to participate in NAEP. Still other SD and/or ELL students selected by NAEP may not be able to participate. Local school authorities determine whether SD/ELL students require accommodations or should be excluded because they cannot be assessed.
See additional information about the percentages of special-needs students identified, excluded, and assessed at the national level.
Differences between scale scores and between percentages that are discussed in the results take into account the standard errors associated with the estimates. Comparisons are based on statistical tests that consider both the magnitude of the difference between the group average scores or percentages and the standard errors of those statistics. Throughout the results, differences between scores or between percentages are discussed only when they are significant from a statistical perspective.
All differences reported are significant at the 0.05 level with appropriate adjustments for multiple comparisons. The term "significant" is not intended to imply a judgment about the absolute magnitude or the educational relevance of the differences. It is intended to identify statistically dependable population differences to help inform dialogue among policymakers, educators, and the public.
Users of this website are cautioned against interpreting NAEP results as implying causal relations. Inferences related to student group performance or to the effectiveness of public and nonpublic schools, for example, should take into consideration the many socioeconomic and educational factors that may also have an impact on performance.
The NAEP scale makes it possible to examine relationships between students' performance and various factors measured by NAEP. However, a relationship that exists between achievement and another variable does not reveal its underlying cause, which may be influenced by a number of other variables. Similarly, the assessments do not reflect the influence of unmeasured variables. The results are most useful when they are considered in combination with other knowledge about the student population and the educational system, such as trends in instruction, changes in the school-age population, and societal demands and expectations.
Return to the U.S. history subject information.