Long-term trend (LTT) assessments are administered according to the frameworks and assessment practices in force during the 1970s and 1980s, and are conducted every four years. LTT was most recently administered in 2012, and is next scheduled for 2016. While national main and state assessments are administered to grade-level student samples (grades 4, 8, and 12) during a single field period, long-term trend assessments are administered to age-based samples (ages 9, 13, and 17) during different periods throughout the school year:
For more information about the differences between national main and long-term-trend assessments, see the page titled What Are the Differences Between Long-Term Trend NAEP and Main NAEP?.
See the page titled Long-Term Trend for additional information about how the long-term trend assessments fit into NAEP.