Existing approaches to integrating ITS and CSCL environments have not attempted to model the collaborative interaction between human learners in order to exploit its pedagogical potential. We present an approach to modelling such interactions and students' underlying beliefs, within the framework of a CSCL environment designed for learning the concept of energy in physics (C-CHENE). The environment is based on flexible structuring of the collaborative interaction using a specially designed communication interface, and a dialogue grammar. We propose three types of automatic guidance that could be provided on this basis.