This preliminary study aims to understand how social presence, cognitive presence, and teaching presence in the Community of Inquiry framework (CoI) might explain online interactions on a discussion forum in a 10-week course. Online questionnaires were used to report students' levels of social presence, cognitive presence, and teaching presence. The results of the questionnaire were correlated with the amount of student online participation measured by the number of discussions created and replies to posts in an online forum. The results showed that cognitive presence was positively associated with the number of discussions created, while social presence and teaching presence was not. The findings suggest that improving cognitive presence may increase the number of online discussions initiated, but was not correlated with continuing discussion in the forum. The present study helps shed light on how the elements of CoI interact differently with student online behaviours of discussions initiated and follow-up posts.