I would like to create one assignment and assign to the whole cohort but have the ability to remove this assignment from appearing on one or two students gradebooks?
Yes, Kate, you can accomplish this through the use of differentiated assignments, as described in How do I assign an assignment to an individual student? You will need to assign the assignment in question to all of the students except those few who will be excluded. The linked lesson explains this process for a single student. In this case, you'd remove "Everyone" from the Assign to field and select each of the students who will receive the assignment from the list.
If you only need to excuse those few students, and don't mind having the assignment appear in their gradebooks but not have their grade count toward the total, you can enter "excused" or EX for those few students instead--and this is much easier. Please refer to How do I excuse an assignment for a student in the Gradebook? for instructions.
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