Researchers used targeted search criteria to identify and screen more than 7,400 relevant studies on arts education interventions in education research databases and clearinghouses. Of those 7,400, 286 reports were reviewed by What Works Clearinghouse-certified reviewers. Reports were classified according to definitions of ESSA tiers of evidence. To gain a fuller picture of findings across all well-designed studies, researchers then recorded the magnitude of effects from 20 studies of arts education interventions and meta-analyzed those effect sizes. 

1. Researchers developed a logic model describing the features of arts education and developed search criteria that would be used in two research database searches. 
2. They conducted two searches of educational research databases and clearinghouses to identify reports about the implementation and impact of arts education interventions. Both search efforts focused on research reported since 2000. The second search incorporated additional arts education terms to identify as many reports in scope as possible. The number of relevant reports found through these searches was 7,405. 
3. The search was refined. Researchers screened abstracts and then full-text documents with a focus on finding empirical studies with data about student outcomes in prekindergarten through Grade 12.  Abstracts and texts deemed out of scope were removed. 286 reports of studies were then reviewed by What Works Clearinghouse (WWC)–certified reviewers. 
4. Researchers examined the reports that contained studies of arts education interventions and classified the studies according to definitions of the ESSA tiers of evidence (Tiers I–IV). 
5. To gain a fuller picture of the research findings on arts education interventions across all the well-designed studies, researchers  recorded the magnitude of effects from 20 studies of arts education interventions and meta-analyzed those effect sizes.