The school or district license
A school license or district license allows a number of teachers and their students to use the features given by a license.
Each license is assigned to a registered DataClassroom user to administrate it. This person need not be a teacher. They will mostly use their Account page to manage the license.
Once a license has been purchased, by PO or by credit card, then an organization (referred to as "School" in DataClassroom menus) will be created, and the owner of the license can add Members to that organization.
This is done via the Account page where the license details are shown:
Teachers can be added and removed with the Add/remove teachers button, using their email addresses as references.
If a teacher has not created an account, their account will be created for them in this process, and they will receive an email notification.
The teachers added in this way will be able to use the licensed features, as will students in any classes they create.