In collaborative learning, group awareness is a central issue. Being aware of the group's perceptions allows an adequate regulation of the activity. Our research explores whether a social robot can provide the necessary awareness. This study evaluates the usability and acceptability of a social robot used in such a role. The robot can express emotions and move according to territoriality principles, leading to a novel communication strategy. We designed and evaluated a learning situation where a Cozmo robot is included in a project meeting. As an awareness tool, it moves and expresses specific emotions that represent individual and group feelings to regulate learner communication behaviors.