This paper presents a mobile serious game, which exploits the Socio-Cognitive Conflict (SCC) by means of a game with the aim of supporting preschool and primary school children in understanding two important concepts: (i) topographical orientation, and (ii) recycling. In fact, an important competency that children deal with is the topographical orientation, particularly as regards the relativity of the objects positions with respect to a specific point. To reach this goal we have designed and developed a serious game for mobile devices (e.g. tablets), where kids need to move a character in a grid, with the aim of helping it in associating specific garbage to the right recycling container (taking into account the relative position of the character and of all the objects in the grid). Such a character represents a humanoid robot named MecWilly. We have conducted a first assessment of our serious game by involving six preschool and primary school kids. The first result we have obtained show that kids were very interested in playing such a game and in experiencing more game levels. Further experimentations have been already planned and will be conducted in three primary schools, stressing the SCC by contrasting the mobile serious game with a similar version of the game played by interacting with humanoid robots.