The use of Augmented Reality (AR) technologies is currently being investigated in numerous and diverse application domains. In this work, we discuss the ways in which we are integrating AR into educational in-class activities for the GAIA project, aiming to enhance existing tools that target behavioral changes towards energy efficiency in schools. We combine real-time IoT data from a sensing infrastructure inside a fleet of school buildings with AR software running on tablets and smartphones, as companions to a set of educational lab activities aimed at promoting energy awareness in a STEM context. We also utilize this software as a means to ease access to IoT data and simplify device maintenance. We report on the design and current status of our implementation, describing functionality in the context of our target applications, while also relaying our experiences from the use of such technologies in this application domain.