This paper discusses learning from a project that set out to explore how the general public perceived the value of public art in the context of urban regeneration of a city centre space. Whilst not set up explicitly as an action research project, the paper discusses the way in which participatory public art projects of this kind can be understood and valued as action research processes. The paper is set within contemporary debates about urban development and new genre public art, and is based on a project that deliberately set out to challenge and interrupt conventional "ways of seeing" about urban design and redevelopment and so provide a different context--"a creative action space"--for public involvement. The project focused particularly on the role of children and how "playfulness" and the input from children might activate alternative possibilities for imagining urban space as a key element to a "liveable" urban realm. The paper discusses different levels of learning that arose from people's experience and engagement with the installation and draws conclusions about the role of art in urban regeneration. (Contains 3 notes and 6 figures.)