I have an idea where I would present a research topic for a Diigo class group. Each student is then required to find one link per week and post comments to two of their classmates each week as well. Is there a way to create the "Week 1" topic for the students and then have them post all their links and comments within that topic discussion? These categories group discussion, links, and comments would keep the group much more organized.

Thanks for the suggestions. I'm excited about the tagging feature, and think that this will be the best way to organize the group. If anyone is interested, I will be presenting a live Ustream broadcast tomorrow (Thursday, June 7th) at 4pm EST on how I plan to incorporate this Group bookmarking/collaboration into my curriculum. You can view the live stream on my Ustream channel at: http://www.ustream.tv/channel/signal-flow. This will be my first broadcast!