The Impact of State Laws and District Policies on Physical Education and Recess Practices in a Nationally-Representative Sample of US Public Elementary Schools
Odds of schools meeting recommendations for PE and recess increased if they were in states or school districts having a law or a policy requiring/encouraging it. State policies are more influential than district policies in regards to recess. Schools with a majority of Caucasian students were more likely than all other racial/ethnic groups to have daily recess. Schools with highest free and reduced lunch eligible populations were less likely to have 20 minutes of recess daily.
Source
Archives of Pediatric Adolescent Medicine