I would like to change the percentage of the overall grade given to an assignment. How do I do that?
Are you talking about an individual assignment with a Display Grade as Percentage or the Assignment Group percentage?
For an individual assignment, you can edit the assignment and change the points available which will change the percentage that shows in the grade book.
For the Assignment Group, you can edit the Assignment Group Weights by click the Setting icon (three vertical dots) in the Assignments page and selecting the Assignment Groups Weight option.
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