I think that while this might be useful for teachers, it might be more sustainable if courses were stored in a version controllable medium to facilitate multiple collaborators.
My initial thought was to actually use GitHub to store the content. Either on Markdown or JSON - to have some version control. I like how Exercism [1] does it. But I thought it would be hard for teachers - unfamiliar with Git - to update lessons.
Then, I thought about implementing a version control system for the project but I felt I was overcomplicating things for an MVP. But I like the idea of having some kind of version control to improve collaboration.
You could also have a cloud service to store the project files, and then the teachers can just login to the editor and click save to upload their latest copy of the course.