Hi Dave,
Very cool to find out about early OpenSim projects especially with students at that age (The other aspects of the project are also amazing). Your comments about SL are right on target as well. I spent 4 pretty solid months in SL networking with educators, purchasing land and building etc. but found the teen/adult grid barrier to be a major stumbling block. I did manage to stumble across the Immersive Education group which pointed me in the direction of OpenSim as well as Wonderland and Croquet. I have set up local servers in my basement running each of these, (running is perhaps not the best term…brisk walking might be better.) As platform stability increases and more “open-grid connectors” appear to allow isolated Sim installations to interact, I think this will take off. I am concentrating mostly on OpenSim and am exploring a variety of things related to mathematics K-12 that can be made more engaging in a 3D virtual environment. If there comes a time when you think I might have something you could use, everything I do is open and I would be happy to share.