Under the No Child Left Behind Act, districts and schools must break down test scores by subgroups to determine whether all students are making adequate yearly progress.
Subgroup categories: u Students from major racial and ethnic groups, typically, African-American, Hispanic, white non-Hispanic, American Indian/Native Alaskan, and Asian/Pacific Islander u Economically disadvantaged students u Students with disabilities u Students with limited English proficiency
Districts and schools may choose not to count subgroups that are so small they are statistically unreliable for accountability purposes. Those numbers, known as an N-size, differ by state, based on approval by the U.S. Department of Education, and range from 5 to 75.
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