Child characteristic psychology studied in depth from the 18th century, is the basis for analytical studies on their spatial perception to improve the design of kid-friendly spaces. In the seventies of the last century, these studies extended from kindergartens to the city through children's playgrounds. There is currently a specific regulation for the design of these architectural typologies that establishes the need to confine the child in enclosed spaces for their safety and the proper functioning of the adult environment. From the analysis of these regulations, the main theories of the New Pedagogy, and the architectural experiences that have been developed in this sense, this research aims to open a debate on the need to expand the concept of the user of the contemporary city to encompass also the needs of the child as a citizen with full rights. In this way, the theories that have served as the basis for designing educational and play spaces can become parameters to influence contemporary urban and architectural design. Following Guattari’s concept of Ecosophy, the following article proposes to incorporate the needs of minorities, in this case, the children, into the design of sustainable cities.