Abstract-Despite the efforts and global policies to achieve universal primary education, there are still 58 million children, roughly between the ages of 6 and 11, out of school globally. Although previous studies showed the value of serious games for learning, not enough efforts were made to apply serious games to reduce children illiteracy. Understanding the complexity of this problem, we put together a multidisciplinary research team, and an industrial partner, to work on the design of a serious game for children without access to school. In this paper, we present the preliminary results of our case study, showing the main design challenges faced to develop such tool and proposing solution to overcome those issues. We aim to call the attention of the research community about the urgent need of more studies in this field and we argue that our results could be used as starting point for taking forward future work in this direction.