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1970-2012 Trends (Long-Term Trend Assessment)

Since the early 1970s, the National Assessment of Educational Progress (NAEP) has monitored student performance in mathematics and reading through long-term trend (LTT) assessments. These assessments measure students’ educational progress over long time periods to look for and monitor trends in performance. Results from the LTT assessments are based on nationally representative samples of 9-, 13-, and 17-year olds.

2012 Long-Term Trend

Assessment Content

Unlike the main NAEP assessments, which develop assessment instruments that reflect current educational content and assessment methodology, measuring trends in student achievement over time requires that LTT assessments remain consistent.

However, in 2004, changes were made to the LTT assessment design, and a study was conducted to ensure that results under the new design were comparable to the 1971–1999 results.

The LTT assessment measures students’ knowledge in mathematics and reading. Survey questionnaires, administered to students, teachers, and school administrators, who participate in an LTT assessment, are used to collect and report contextual information about the students’ learning experience in and out of the classroom.

Main NAEP Assessments and LTT Assessments

Explore the differences between NAEP and NAEP LTT.

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How LTT Results Are Reported

Student performance on the NAEP LTT assessment is presented in two ways: scale scores and performance levels

  • Scale scores represent the average performance of students who took the LTT assessment in mathematics and reading. Scores are aggregated and reported for the nation and groups of students based on gender, race/ethnicity, etc. 
  • Performance levels are reported as the percentages of students attaining specific levels of performance corresponding to five points on the NAEP long-term trend reading and mathematics scales (150, 200, 250, 300, and 350).

How to Interpret Results

See how to interpret the results of the LTT assessment, including the potential effects of exclusion on assessment results.

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Last updated 05 July 2018 (AA)