Understanding Collaborative Digital Media Design in the 3D CVE students were more active in their own learning, that they were forced to overcome problems by sharing solutions. Instead of deferring to the teacher for solutions to problems, they were now participating in problem solving of their own ac- cord. The process of problem solving could be seen through the process of reification, which together with the dual process of participation allowed negotiation of meaning, forming a shared repertoire (Wenger, 1999). As a learning community, the students partici- pating in the study shared a history of participation and learning where members had different roles as master and apprentice and there was a progression through these roles, along learning trajectories. The students' designs comprised the outcome of the activities and thus served as the shared rep- ertoire of the community and as the indicators of a learner's movement along a trajectory (Tolsby & Sørensen, 2000). munity members were reified within the shared repertoire as documents, plans (sketches, email and chat communications) and the 3D constructions. Membership involved reconciliation of boundar- ies and creating bridges across the landscape of practice. The boundaries were reified with explicit markers of membership, such as national identity (e.g. national flags in the constructions), or with boundary objects, connecting and coordinating different practices and communities (such as teleportation links connecting constructions sites of subgroups within a bigger group). During the project, the students used various tools to mediate their activities. Some of them used blogs, paper sketches and pre-built building blocks in Active Worlds for further customization and copying. They put information about their design activities and ideas in the blogs and on the building sites as notes and design fragments. In this way, the students put `experiences into thingness'