In this article we describe the CALSIUM framework to elicit children's contributions and perspectives in the design of an online game for enhancing social skills of children. This study advocates a participatory design approach that emphasizes the active involvement of users at the early part of the design process. The children play-tested the game prototype and participated in focus group discussions. Using storyboarding, a low-fidelity prototyping technique, they developed design concepts and ideas which were translated into design directions for the development of the game. The data collected were used to glean insights into the likes and dislikes of children and to analyze the opportunities and challenges in engaging children as users, testers, informants, and design partners. Besides stretching children's creativity and critical thinking on the game design, the children's cognitive understanding of social knowledge was enhanced, evident from the design artifacts produced.