When a teacher no longer requires access to a subject, they can be removed by a co-teacher or they can remove themselves.
Teacher enrolment is managed on the Students page.
Click Manage co-teachers on the left side of the page to view the list of teachers currently enrolled in the subject.
Hover over the teacher's name or email to reveal the Remove option to the right of the teacher's email address. Click Remove. This action is effective immediately; no prompt will appear.
Protip: You can also remove yourself this way.
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