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If you want to set a default grade for a certain assignment, use the assignment drop-down menu. This will allow you to input scores for students who do not have scores or to overwrite already entered scores.
Note: When Multiple Grading Periods are enabled in a course, you cannot set a default grade for any assignment that has at least one student in a closed grading period.
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Open Grades
In Course Navigation, click the Grades link.
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Open Assignment Drop-down Menu
Hover over the assignment title and click the drop-down menu.
Set Default Grade
Click the Set Default Grade link.
Create Default Grades
Type the default grade value in the text box [1]. If you would like to overwrite existing grades for the assignment, select the Overwrite already-entered grades checkbox [2]. Click the Set Default Grade button [3].
Verify Default Grades
Click the OK button to view the new default grades.
View New Grades
Default grades are automatically entered for all students who do not have a grade. Grades can be changed by clicking the default grade and typing in an updated score.