 
"Theoretical Investigations" argues for a particular vision of Computer-Supported Collaborative Learning (CSCL), centered on a specific paradigm of collaborative learning, which is explored by a sequence of reprints from the "International Journal of CSCL." 
A series of other essays reviews contributions to a theory of group cognition as foundational for CSCL research and practice. These papers are gathered from reports of the Virtual Math Teams (VMT) research project.