There is a growing psychological literature on children’s environmental choices and how they may affect self-regulatory processes such as emotion regulation. While the school playground is an important environment for the socialization of children, there are relatively few studies of how children use these outdoor play environments and of what guides their choices of where to play. A total of 31 children in third grade (21 girls, 10 boys), 19 children in fourth grade (7 girls, 12 boys), and 70 children in fifth grade (28 girls, 42 boys) were shown models of two separate school playgrounds that contained different configurations of grass, asphalt, trees, and play structures. Neither model resembled their own school playground, and these models contained no social density information about where most children might choose to play. Participants were asked to indicate where they would choose to play on each of the model playgrounds when experiencing each of six different emotional states (excited, happy, bored, sad, angry, and nervous). Choices of where to play were categorized as public areas (wide open areas central to the playground) or private areas (along the periphery of the playground or hidden behind visual barriers). After indicating where they would play, participants were asked to elaborate on the reasons for their choices. Reasons were coded into seven categories: emotion regulation, activity/physical feature of the playground, social, solitary, nature, combination, or other. Children chose public areas more often for positive mood states and private areas more often for negative mood states. They gave more activity/physical feature and social reasons for the location choices with regards to positive emotional states, and more emotion regulation and solitary reasons for the location choices with regards to negative emotional states. Thus, children’s environmental choices appear to be linked to their affective states and may, in the case of negative emotions, contribute to successful emotion regulation.