Computer conferencing has been increasingly incorporated to academic routines, either in distance learning or in the regular classroom, as a support. Nevertheless, the literature has focused on synchronous CMC; its few incursions into asynchrony refer to discussion lists or limit themselves to defining the forum. To fill up such a gap, this study focuses on a private forum held simultaneously with classroom learning by undergrads in Electrical Engineering, at PUC-Rio. Its objective is to describe and analyze, quantitative and qualitatively, the role of the forum as a discursive experience, investigating how interaction and knowledge construction take place; the possibility of characterizing the forum as a genre; and the effect of teacher`s intervention in the process. Inspired by sociointeractionism, it analyzed participation and interactional direction, the topic framework, social and cognitive aspects signaled by linguistic devices that represent affect, attitude, metacognition, lexical and syntactic complexity. Results suggest that future studies need to address the forum within the paradigm of genre study. It also suggests that the forum is a genre and functions as a community of inquiry, leading to critical thinking by means of dialogical discursive and literacy practices, learning of coesive ties in writing, and the development of collective intelligence. Apparently, it contributes to the construction of the social and professional identities of the participants.