This paper deals with visual digital collaborative tools for public participation in urban design. First it addresses the problem of the diversity of skills and knowledge levels of all the actors involved. The main focus is on exploring Urban Experimental Lab (Voigt, Kieferle, Wässner, 2009), developed for public participation in urban design, shifting the research focus towards the questions of educating both lay and different professional public through this process. Public participation in urban design is seen as an opportunity for lifelong urban design learning, offering a wide variety of different actions, problems and educational elements. All the participants are expected to improve their knowledge levels through participating in design process.