I liked Wikiversity because it is so similar to Wikipedia and students everywhere already understand the set up and usage of “Wiki.”
https://en.wikiversity.org/wiki/Wikiversity:Main_Page
Wikiversity is a site much like Wikipedia where it is open source and anyone can edit it and look at it at anytime. Unlike Wikipedia which is just information, Wikiversity offers resources and research similar to a text book.
As you said in class, now that I understand what is going on more, Wikiversity could easily replace a text book for a certain topic in a classroom. The upside to this is that Wikiversity is free and as many students and teachers know, text books are not free… or cheap.
Fact checking, I think, would be the biggest challenge for this open source only because people are able to edit it or add to it at any point. It would probably be smart to take the extra step and fact check with a second source to make sure all information is correct.