By virtue of the non-profit nature of school education, a professional virtual community composed of teachers provides precious data to understand the processes of knowledge sharing and creation. Guided by grounded theory, the authors conducted a three-phased study on a teachers' virtual community in order to understand the knowledge flows among community members from different organizations. This study also portrays the process of knowledge sharing and creation for teachers participating in virtual teams of a teachers' professional community. The resulting model articulates causal conditions, action/interaction strategies, consequence, and contextual environments. The concept of knowledge buckle is derived to connect the knowledge transfer among socialization, externalization, and combination activities.