Using NAEP Mathematics Subscale Trends to Evaluate Common Core Effects

Using the context of the Common Core State Standards for Mathematics (CCSS-M), this study demonstrates how an analysis premised on NAEP mathematics subscales can inform educational policy research. Using data from 2000 to 2019, we show that achievement trends have diverged by subscale during the Common Core era in a way that did not occur during the No Child Left Behind era. The divergence of trends by time and subscale suggests that the CCSS-M may have disrupted and slowed the prior rate of gains in mathematics achievement. The gaps between students at the 90th and 10th percentiles of the achievement distribution have also widened significantly. We offer examples of additional targeted analyses necessary to make sense of these results.