Hi Kay,
You are the first responder to my lonely question.

I’m not sure InCopy would be the right solution for your graphic design students to use for collaboration. It does allow InCopy editors to open InDesign documents at the same time a document is actively being used by an ID user, the IC user can “check out” text files and make changes, then save and check the text file back in again. But InCopy users only have the text editing tools. They have none of the graphic tools, ie. they cannot resize a text box or anything else.

As far as I know, an InDesign doc can only be opened by one ID user at a time.

Brian