As knowledge creation starts to venture into most social sectors, there arises the necessity of transforming schools into knowledge building communities that allow students to take a life of knowledge work. The problem comes in, how does knowledge work actually work, particularly in a school context?

The purpose of this study was to address the knowledge dynamics in a KBC by investigating the dynamic conceptual and social structure of scientific inquiry in Knowledge Building (KB) environment and their influences to conceptual change/growth. This was accomplished through the content analysis and Social Network Analysis (SNA) of the online discourse about optics in a Grade 4 KB classroom supported by Knowledge Forum. Within the communal knowledge space, there emerged 28 inquiry threads defined as a cluster of notes that addresses a shared principal problem and constitutes a conceptual stream in discourse. These inquiry threads were interlinked with each other as a network by the bridging notes that concurrently addressed more than one principal problem. In those intensive inquiry threads, noticeable conceptual change was observed as a complex growing path. Communal KB activities in the inquiry threads were closely related to members’ personal knowledge growth reflected in their individual portfolios. SNA of learners’ roles in different inquiry threads showed that the KB community had grown distributed expertise. Learners’ influential statuses were derived from their high level engagements in KB, such as addressing explanatory problems and pursuing explanations at higher epistemic levels, generating, improving, and justifying personal ideas, introducing and making constructive uses of expert resources. Based on these analyses, this article proposed a design for promoting learners’ collective reflection of knowledge building as a way to help bridge community knowledge building and personal learning and achieve higher level of epistemic agency.