The NAEP 2008 long-term trend assessment was administered to students aged 9, 13, and 17 who were enrolled in public and nonpublic elementary and secondary schools throughout the nation.
Approximately 26,600 students took the reading assessment, while about 26,700 took the mathematics assessment.
NAEP does not, and is not designed to, report on the performance of individual students. Instead, it reports average results for groups of the student population from representative national samples. For example, NAEP reports results for male and female students; Black, Hispanic, and White students; and students in different regions of the country. Samples are selected using a complex sampling design.
NAEP has always endeavored to assess all students selected as a part of its sampling process, including students who are classified by their schools as students with disabilities (SD) and/or as English-language learners (ELL). The decision to exclude any of these students is made by school personnel. School personnel are encouraged to use inclusion criteria provided by NAEP and may discuss their inclusion decisions with NAEP field staff. See tables summarizing the percentage of students identified, excluded, and assessed in long-term trend.