| Conversation has long been recognized as a core vehicle for learning. In recent years, evolving web technologies have opened the door for learning conversations distributed across time and space and led to a new generation of web applications that emphasize online sharing and collaboration over the centralized distribution of information. Despite this, existing approaches to designing online learning conversations have been limited in their efforts to help learners generate knowledge because of a separation from individuals' local practices.; This dissertation uses Polanyi's schematization of knowledge as a tacit-explicit duality as a theoretical lens for developing a comprehensive theory of knowledge building that links online conversations with local practice. Following his claim that the tacit and explicit dimensions of knowledge are mutually reinforcing, inseparable and irreducible, I adapt Nonaka's Dynamic Cycle of Knowledge Creation to create my own framework for knowledge building that links online conversations with local practice through a dialectic between the complementary processes of Externalization (collective reflection) and Internalization (conscientious practice). I then explore the implications of this framework for the design of online conversation spaces by compiling and adapting a set of eight principles for designing online conversations that foster an effective process of Externalization, thus promoting the knowledge-building spiral.; These principles were subsequently used to inform the design and development of online discussions to support student teachers in the field, and the effects of different strategies for instantiating these principles were examined. Specifically, the characteristics, use and effectiveness of three different common referents (a video, a theory and a metaphor) were investigated. The results suggest several refinements of the theory and areas in which future instantiations can be improved. To be effective, a common referent must have, or be presented with, a conceptual frame for interpretation. The use of a metaphor as a referent was identified as having particular promise as an effective referent (if employed with the appropriate conceptual framing) due to participants' willingness and ability to make cross-domain connections. Additionally, the findings highlighted the importance of actively promoting inter-participant dialogue and using redundant design strategies to increase the probability of a faithful instantiation. |
