Green space has beneficial effects on several cognitive and behavioral aspects.

[ehsnils]

I'm not surprised that this is the case - how fun is it for kids to live in an environment only consisting of concrete and rectangular bricks?

 

Our results indicate that residential green space may be beneficial for the intellectual and the behavioral development of children living in urban areas. These findings are relevant for policy makers and urban planners to create an optimal environment for children to develop their full potential.

https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003213

[ammcinnis]

... residential green space may be beneficial for the intellectual and the behavioral development of children living in urban areas.

Makes sense, especially if you think about it in evolutionary terms.