Use Excuse/Include Grade exclude a student's grade in a specific item or component of the course. This is a helpful method of not penalizing students who have been excused from an assignment. An item can be added back in the grade calculation by again selecting Excuse/Include Grade from the cell's drop-down menu.
Select Gradebook from the Tool Menu of your site.
A + icon (Grade has been excluded from grade calculations) will appear in the affected cell, and the score will have a strike-through, indicating that the score is not being calculated in the student's course grade.