In the classrooms at school, when a group of students is working in a predetermined task, the teacher or the tutor identifies some problems related to collaboration by observing the students’ behavior. While interacting, people interchange messages composed of speech, actions and gestures, as the wordless messages emphasize, support or even substitute speech. In 3D collaborative virtual environments (CVE), the user’s graphical representation, an avatar, is the means to express this nonverbal communication (NVC). The authors’ proposal is that, like in a real learning scenario, by the observation of specific NVC cues, indicators of collaborative interaction can be inferred to an extent that they can be used to foster collaboration, if necessary, in a learning task situation. The various NVC cues that have been selected for that purpose and their corresponding collaborative learning interaction indicators will be presented. An exploratory study that consisted in the analysis of a real life situation during a collaborative task accomplishment, directed to the development of an experimental 3D CVE desktop application that allows avatars’ display of NVC cues, will be discussed.