Virtual environments are now becoming a promising new technology to be used in the development of interactive learning environments for children. Perhaps triggered by the success of computer games, VEs are now seen as an emergent and engaging new way by which children learn experimental sciences and other disciplines. Inhabiting these IVEs there can be agents or intelligent characters, that are responsible for events that happen in the environment and make it not predictive or completely controlled. However, to build such environments, in particular if populated by synthetic characters, one needs to carefully address the problem of how do the learners respond to the characters in the virtual environment. Do learners like the characters? Do learners identify themselves with characters in virtual en