This paper examines the way bachelor’s degree students in education in an online environment (FORSE, CNED) use a discussion forum, and how a virtual community of practice (CoP, Wenger, 1998/2005) emerges from their written interactions. We gathered and analysed these interactions, which are distributed in one academic year on three periods. Moreover the students were given a questionnaire assessing their practices and opinions on the forum. Three main dimensions were investigated: the actual use of the discussion forum tool; the students’ awareness about each other (actions, thoughts); the extent a virtual CoP can emerge and develop. Results show, first, that the forum tool shapes the communication among students; second, that identity and self-introduction schemes are mainly delivered in the first phase. Eventually, several help or self-organizing behaviours, as well as different levels of involvement were found, supporting Wenger’s theory.