The unintended effects of the Common Core State Standards on non-targeted subjects

Abstract

School curricula are a central tool of education policy and are typically reformed to improve achievement in specific subjects. Such targeted reforms may also affect learning in other domains by shifting instructional priorities. We study the adoption of the Common Core State Standards (CCSS) in math and English language arts in the United States and estimate their effects on achievement in both targeted and non-targeted subjects. Using models with state and year fixed effects, and individual-level student achievement data from NAEP, we show that the CCSS had zero to modest positive effects on student achievement in targeted subjects, and a negative effect on student achievement in non-targeted subjects. This negative effect is concentrated in science and among students in elementary school where teachers have the most flexibility to shift instructional focus. Our findings underscore that evaluating targeted education reforms without accounting for non-targeted outcomes may provide an incomplete picture of their overall effects.