This report presents results from a new quantitative synthesis of research on the effectiveness and validity of test accommodations for English language learners (ELLs) taking large-scale assessments. In 2006, the Center on Instruction published a review of the literature on test accommodations for ELLs titled "Practical Guidelines for the…

We examined how much agreement there was between scores from large-scale mandated assessments and report-card grades for 14,776 students in grades 3, 6, and 9 of a district in which conditions were conducive to alignment of assessments. We found significant mean differences between internal and external assessments: effect sizes were 0.29 to 0.63…