I'm a strong believer in using wiki technology to improve student writing (it's in fact what brought me to Drupal !). I'm working on improving a collaborative writing feature. It currently uses basically Open Atrium's notebook feature (revisions and inline diff) with the ckeditor wysiywg and puts comments on a separate page with talk module. I'm looking for some ideas / help.
One addition I'd like to add is
BETTER WORKFLOW: I'd like to improve this in order to improve the workflow with teachers as students create drafts. What am wondering is what might be the best approach to building revision-based workflow? I'd like teachers to be notified when students feel like their draft is ready/finished. Perhaps imagining 2-3 drafts.
-Perhaps it could be done with something like the status bar with things like "Drafting" | "Ready for comments" | "Finished" ?
-Or a flag like "Ready for Teacher Comments"
Any other thoughts on how to build and improve this?

Comments
Workbench
Hi,
I would think that the workbench module could help you out. I am not sure how it would integrate with OpenAtrium. http://drupal.org/project/workbench
You can assign yourself or students as editors who can review other students work. Each change is automatically diffed and the student can submit a version for review which then notifies the editor.
Sounds like a great student/teacher tool. Keep up the great work.
Workbench Drupal 7 & Open Atrium Drupal 6
Unfortunately Workbench is only for Drupal 7 and Open Atrium is using Drupal 6 core.
I would love to roll out my new site that I am working on in D7 with Workbench but for right now I am still using Workflow, Revisioning and an action that sends email under D6.
I'm not familiar with Open
I'm not familiar with Open Atrium, but I've achieved similar workflows with either flag + flag actions or the rules module.
Teacher Marking Filter?
Flag approach seems to be working fine so far.
Any ideas on how to add a specific revision / filter for teacher corrections? It currently highlights Added | Changed | Deleted.
I'd like to add something like "Needs Correction" where a teacher could highlight text that would show up in red.
Thoughts? Approaches?
Perhaps could setup a plugin / button for ckeditor for highlighting "Needs Correction" and "Meaning Unclear" Etc, which would create a markup that could use a filter to output as colored text blocks.
Other Thoughts? Implementation approaches?
http://drupal.org/project/sti
http://drupal.org/project/sticky_notes I looked at this awhile ago for setting sticky notes for a student to read ur feedback contextually. It's not highlighting unfortunately
Ex Uno Plures
http://elmsln.org/
http://btopro.com/
http://drupal.psu.edu/