RESEARCH LIBRARY

This article reports findings from the largest-ever randomized controlled trial of a growth mindset program in the United States in K-12 settings. The study combined a test for cause-and-effect (a randomized experiment) with a sample that enables claims about an entire population (a nationally representative probability sample). The study found that a short (less than one hour), online growth mindset intervention—which teaches that intellectual abilities can be developed—improved grades among lower-achieving students and increased enrollment in advanced mathematics courses among both higher- and lower-achieving students in a nationally representative sample of regular public high schools in the United States. Notably, the study identified school contexts that moderated the effects of the growth mindset intervention: the intervention had a stronger effect on grades when peer norms aligned with the messages of the intervention. In addition to its rigorous design, the study also featured independent data collection and processing, pre-registration of analyses, and corroboration of results by a blinded Bayesian analysis.