Virtual Worlds have become a very popular domain and its high inmersive characteristics can be used to extract infor-mation about the avatars behaviour. In this kind of environ-ment it is possible to obtain interesting data about avatars, such as their exact position in the world, what they are look-ing at (eye-gazing) or what they are talking about. This paper studies how this information, obtained from avatars interactions, can be integrated in order to apply clustering techniques. Monitoring avatars in a virtual world is a useful task that allows the identification of behavioral groups. The meaning of these groups depends on the application domain, for example in educational virtual worlds, they can represent whether students are paying attention to the teacher’s ex-planation or not.