Step 1. Enter the course that you'd like to edit the grade calculation for and select the Course Administration (Gear / Cog)
Step 2. Select the Gradebook Setup option from the dropdown menu.
Step 3. Select the Edit link for the Course Total from the list of grade items.
Step 4. Select the Edit Calculation option from the dropdown
Step 5. Enter ID numbers for the activities that you would like to use in your Calculation. These ID numbers are your preference, so you can add whatever works best for you.
Step 6. Select Add ID Numbers and this will add the ID numbers you created to the activities.
Step 7. Create the Calculation. Just like when using formulas in Excel you would add the formula to create the grade calculation so that only some activities get counted towards the course total.
E.g =sum([[idnumber]]+[[idnumber]].....etc.)
Step 8. Select Save Changes
Step 9. To check that this is working correctly, on the gradebook setup page, select the view tab.
Step 10. The course grade for each user should now only be calculated by the grades outlined in your grade calculation and not other graded activities within the course.