In distance learning, remote laboratories (henceforth RLabs), allow students to perform real-time tasks on laboratories over the Internet. However, existing tele-operations systems suffer from both the low fidelity of the representation of the remote site that hosts the instrument, and the lack of "group awareness" for collaborative learning during online hands-on sessions. In this paper, we discuss how Mixed Reality systems can improve the fidelity of such remote devices and how group awareness can be achieved. A software architecture for collaborative mixed reality for RLabs based on the MPEG-4 BInary Format for Scenes (MPEG-4 BIFS) is also presented.