The rapid advance of distance learning and networking technology has enabled universities and corporations to reach out and educate students across time and space barriers. Although this technology enables structured collaborative learning activities, online groups often do not enjoy the same benefits as face-to-face learners, and their instructors often do not have time to actively support and mediate the online collaboration. This article demonstrates our capacity to computationally model, analyse, and support online student interaction, in particular knowledge sharing. A unique combination of qualitative analysis and artificial intelligence methods was designed to (a) recognize when students are having trouble learning the new concepts they share with each other, and (b) understand why they are having trouble, so that we might assist an instructor or intelligent coach in mediating group knowledge-sharing activities.