What you want to do is create Sections, not Groups.
In Canvas, "Groups" are for collaborative assignments. Everyone will be working together. You can choose whether to grade the students individually or as a group. I REALLY WISH that the Canvas developers had used the term "TEAMS." It would have been so much clearer. (Seriously, this is a "BIG FAIL.")
"Sections," on the other hand, are used to differentiate among students. For example, you might create a "Section" for IEP students who will get a modified assignment. When you designate a "Section" for an Assignment, only those students will be assigned the work. These assignments will be individual assignments, and each student will be graded individually. Unlike "Groups," these students will not see who the other students in their "Section" are.
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