Limited up to now to the research domain, immersive VR installations have recently become increasingly more popular in real-world settings, including the location-based entertainment market and informal educational institutions (science centres, museums). In these public settings, the two essential properties of a VR experience, immersion and interactivity, are advertised widely in order to attract and motivate visitors. Particularly, the interactive features of a virtual experience are touted even further for their significance to learning; it is commonly considered that a learning environment is more effective if it is interactive. However, little systematic research is available to substantiate this assumption and, to date, there exists no clear evidence that interactive VR applications can bring "added value" to learning, especially in children. I am interested in examining this dimension of interactivity in immersive VEs and its potential and limitations for learning. I intend to study the parameters of the complex relationship between interactivity and learning by determining how interactivity enables learners to construct meaning. My hope is to ultimately contribute to the design of better interaction methodologies in VR systems for formal and informal educational settings.