Background: Class size reduction (CSR) is an enduring school reform undertaken in an effort to improve academic achievement and has been widely encouraged in the United States. Supporters of CSR often cite the positive contemporaneous and carryover effects of Project STAR. Much has been discussed regarding the robustness of the contemporaneous…

This study estimates program effects (English immersion versus primary language instruction using varying degrees of Spanish) upon English and Spanish word identification in the context of changing classrooms (cross-classification) from kindergarten through second grade. Letter-word identification is an important predictor of early reading…