Online three-dimensional (3D) virtual worlds are emerging technologies that offer unique learning opportunities for traditional and distributed education. One of the more popular 3D virtual worlds, Active Worlds, is currently being used as a medium for synchronous and asynchronous distance learning. This investigation presents two exploratory case studies of different, but exemplary educational activities using Active Worlds for formal and informal education. The focus of each case study is to investigate how Active Worlds is being used for distance learning and to determine the type of learning experiences afforded by this 3D virtual environment. Whilst more research is necessary to explore fully the potential of 3D virtual worlds for learning, this initial investigation illustrates how Active Worlds affords opportunities for experiential learning and situated learning within a collaboration learning environment.