The purpose of this paper is to showcase new research that seeks to provide guidance on the heterogeneity of treatment effects by utilizing the variance of demographic differences in state assessments. This study is focused on a simple randomized block design where students are nested within schools, and within each school students are randomized…

Student achievement in literacy and mathematics for students involved in a Spanish language program at a large and diverse school district in Arkansas, were compared to peers' scores who did not participate in the program. The program was implemented to enroll native English speaking students in a Spanish enrichment program (SEP) with the intent…

Background: Cluster-randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…