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Create a new assignment and make the points Zero.
Then set the Submission Type to No Submission.
Then to add the Extra Credit, you can edit this assignment in the Grade Book.
Note: For a zero-point assignment to work for extra credit, there must be at least one positive point value in the assignment group.
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To add extra credit to an already existing assignment, click on the assignment in the grade book and manually enter the combined value of the grade and the extra points.
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You can use the Fudge Points feature within SpeedGrader to add points to a quiz.
For more help with Fudge Points, click here.
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If you make a rubric worth more than the assignment, you can then add extra credit while leaving the original grade unaffected.
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To add extra credit to a rubric in SpeedGrader, you can set one of the fields to above its max value.
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Step 1: Create an assignment group called "Extra Credit".
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Step 2: Create the total weight of all other assignment categories with a total equaling 100%.
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Step 3: Then choose a weight for your Extra Credit assignment category.
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Because the total weight is over 100%, Canvas will not calculate the value of the Extra Credit category if that entire group has no points possible.
You cannot use the Zero Point Value method when using a weighted category.
If you want to add 10 extra credit points, you must create an assignment with a point value and grade it as such (e.g., 10/10).