environment for the children...if children are healthy and happy, they learn better.

(chriskirsch.medium.com, 2018)

This is saying that kids feel safer because they are being supervised by an adult, and when they feel safe, they might want to participate in other things, they might want to speak up, and they also might be focused on their work.

Children are participating in moderately vigorous physical activity.

(chriskirsch.medium.com, 2018)

This suggests that all children should participate because it keeps them safer, improves their well-being, and adults believe that structured recess includes physical activities.