Class Document Library
The class notebook within OneNote is a useful idea, and I would like to see something similar to automatically configure permissions for a document library.
In other words, there would be folders that are editable by both teachers and students (already exists), folders that are editable by teachers and viewable by students (already exists but it is kind of a hack because it does not actually reside within the Team file share and does not sync along with it), folders that are editable by teachers and not viewable by students, and personal folders for each student that the teacher can see and other students cannot.
I often take the time to create one folder in OneDrive or SharePoint for each student in my class and manually configure the permissions so that each student has a personal folder to share with me. OneNote Class Notebook configures this automatically, and I wish that document libraries had an easy way to do this as well.