Teaching with Collaborative Documents

A few months ago Jenna and I had a conversation talking about the need for a more dynamic way for dropbox documents to be passed back and forth between Teacher and Student. We also discussed the need for versioned documents, or documents where students share an assignment and pass the document back and forth student-to-student.

I got another request in this morning form a teacher who said:

"I need to evaluate the students' thinking which is why essay questions are important. They need to get my feedback, alter their answers, and submit for me to grade -- as a study guide, not as an exam."

I responded that he could use the dropbox message feature, or use 'Embed the Web' as a means for collaborative document writing. I mentioned two other exciting services available via Embed the Web that when used in Haiku, can bring collaborative writing to your classes.

I wrote:
"You can have your students work inside of Google Docs and then have
them share the documents with you. You can have them link to the
documents from their dropbox submissions. Google Docs can track
changes and you can both work in the Google Doc at the same time.
Very exciting stuff, but requires google accounts, so it may not fit
your needs.

You could use an application like http://writeboard.com/ to
collaboratively work, and it does an excellent job of comparing
versions and tracking pages. Similar to Google Docs, your students
would need to share the application with you and have accounts in
Writeboard."

That said, I know that there are teachers actively using GoogleDocs in this fashion. I would love to hear from them about their experiences with GoogleDocs, Writeboard or any other web-based collaborative writing services.

What have you found works well? What things should teachers thinking about doing assignments like this be aware of?

-Bryan