Our goal at OfficeHours would be to expand on the exact concept you describe. It seems as though the current idea is to include a button whenever an editor is changing a wikipedia article. That would hook into a modified helper setup where there would be experts on how the wikipedia platform worked. We want to do the same thing, but our user group would in theory include all wikipedia readers and and our helpers would be knowledgeable on subject matter specific to that content. Put in brackets for the moment how people would be labelled as experts or helpers or mentors or whatever the term might be.

Without much work, we could implement an open source version of our platform that could hook into your course management system. And if things work well there, perhaps we could think about other ways to expand the concept.