Create a course with two groups and assign 1 student to one group and one non-editing teacher to the other. Review the default permissions of non-editing teacher to avoid view all the groups. Create an assignment with Separate groups. Log in as the student and do a submission of this assignment. Log in as the non-editing teacher and check the information in the Summary grading screen of the assignment, where there SHOULD NOT be any participant neither submission. Create another group and add there the student and the non-editing teacher Log in as the non-editing teacher and access the grading summary page You SHOULD see a drop down menu Only your two groups SHOULD be listed Check that you can change them and the number of participants and submissions changes according to the group users Remember the last group you selected Go to the course page and return to the grading summary page Check that the selected group by default is the last one you selected