Add an Instructor to a Group

By default, anyone listed as an instructor in a course site won’t appear in the list of users who can be added to a group. Fortunately, it’s pretty easy to make those folks appear on the Add Users list, just check the Show all users regardless of role box in the search space at the top of the group’s Add Users page, and anyone listed in the course (including instructors and teaching assistants) will be available to add.

All User Roles checkbox