Many national and international educational data collection programs offer researchers opportunities to investigate contextual effects related to student performance. In those programs, schools are often used in the first-stage sampling process and students are randomly drawn from selected schools. However, the "incidental" dependence of…

Applied early adolescent researchers often sample students (Level 1) from within classrooms (Level 2) that are nested within schools (Level 3), resulting in data that requires multilevel modeling analysis to avoid Type 1 errors. Although several articles have been published to assist researchers with analyzing sample data nested at two levels, few…

A new national study provides some of the strongest evidence to date to support what many educators and parents of young children already believe, children learn more in full-day kindergarten programs than they do in half-day programs. The findings are based on federal data from a nationally representative sample of 8,000 children in public…