Create Hidden Section for ONLY Teachers to see.
This could be useful for teachers sharing notebooks, or even if a teacher has to take a leave of absence.
Mitch Ravitz commented
This exists but you have to go back and "manage" a notebook. It would be better and more useful if it were created at the same time as the other two sections are created.
This already exists, it's called the 'Teacher only section' of a class Notebook.
You can enable it via the 'Manage Notebooks' section from the Class Notebook app