NAEP trends: Main NAEP vs. Long-term trend
This study compares the measurement of mathematics and reading trends by two separate National Assessment of Educational Progress (NAEP) statistical series. The first series is based on the Long-Term Trend assessment, which dates back to 1969 and assesses students in three age groups: 9-year-olds, 13-year-olds, and 17-year-olds. The other series, now described as Main NAEP, assesses students by grade: grade 4, grade 8, and grade 12. The study’s focus is on average levels of change over the period since 1990 and on a comparison of the two data series over that time period.
The objectives of this research are to (a) compare the trend lines after some adjustments for level and scale only and determine if and how they differ; (b) describe the methodology of each assessment and identify similarities and differences; and (c) attempt to explain any observed differences based on comparable subsets or on special analysis. Subsets considered include grade within age, age within grade, and racial/ethnic groups.