Toward the goal of more rapid knowledge accumulation via better meta-analyses, this article explores statistical approaches intended to increase the precision and comparability of effect sizes from education research. The featured estimate of the proposed approach is a standardized mean difference effect size whose numerator is a mean difference…

Many public and private initiatives have focused on improving prekindergarten (PK) through Grade 12 mathematics education, given that the mathematics content learned before college is foundational for later learning and college success across STEM subjects. Although decades of educational research have studied PK-12 mathematics interventions, the…

Since the standards-based education movement began in the early 1990s, mathematics education reformers have developed and evaluated many interventions to support students in mastering more rigorous content. We conducted a systematic review and meta-analysis of U.S. PreK-12 mathematics intervention effects from 1991 to 2017 to study sources of…