Abstract: Although sociological research has shown the importance of place and environment to children's lives, namely to their health, independent mobility, approach to social problems, social identity, sense of safety, and general impact on inequality and inequity, children are still seldom included in urban planning. As a consequence of this invisibility of children, cities lack safe public places for the multitude of children that live there, to walk, play, and build healthy relationships with the environment. This project aims to tackle this inequity by using a participatory approach to investigate children's relationships with urban public places in the two major Portuguese cities (Lisbon and Porto) and major tourism centers. Both Lisbon and Oporto are interesting case studies as they prepare this year their respective applications for the certification 'UNICEF-friendly city' of UNICEF. Starting from the assumption that children are social actors with valid knowledge and capable of political participation, with a "right to the city", we build from the literature on children's relationships with place and child-friendly cities, understanding "childhoods as socio-cultural spaces", performed by children. Analyzing children's relationship with place from their own perspective, we use an ethnographic, child-centered and participatory approach based on a plurality of methodological resources. The main objective is to understand children's appropriation of urban public places, and more specifically, how these appropriations are related with child-environmental identities (Ma07) and the role played by ICTs, as well as art in these identities; children's confrontation with urban difference (including that difference associated to foreigners and tourists); children's sense of safety and relationship with urban violence; children's care for the environment and relationship with the non-human world; children's agency and sense of community; and children's practices of transgression. Considering children as "experts", we aim to transpose this data into urban planning by fostering dialogue with the community and decision-makers in order to design possibilities for a child friendly-city.