Verify that you are using the Natural Aggregation Method
Natural has replaced Sum of Grades and behaves exactly the same with two exceptions: it provides the option to specify weights and allows you to setup and use extra credit more intuitively than any other current aggregation method.
PLEASE NOTE: If you discover that your aggregation method is not already set to Natural and you already have grades in the gradebook, be aware that your gradebook will be recalculated when you switch methods (as would be the case anytime you switch methods). If you are unsure or have any questions or would simply like assistance, contact your Instructional Technologist.
Click Gradebook Setup in the Administration Block.
Click the first Edit link on the top-level course gradebook item.
Click Edit settings from the menu that appears.
Under Grade category, make sure Aggregation is set to Natural. Then click Save changes at the bottom of the page.
Adding an extra credit item
From the Setup (categories and items) view, scroll to the bottom of the list and click Add grade item.
Complete the "add grade item" form the same as you would for any other grade item. Then click Save changes.
After you add your grade item, you will notice that it adds the value of that item to the overall course total. In order to correct this and have it treated as an actual extra credit item, scroll down to the new item you just created and click Edit.
On the grade item settings page, scroll down to the Parent category section and you will see a checkbox labeled Extra credit. Make sure this box is checked. This will tell Moodle to treat this item as true extra credit. Click Save changes when you are done.
After saving your changes, you will notice that your extra credit grade item is no longer being factored in to the overall course total and is calculated as extra credit.
If you have any questions, concerns, or would like some assistance with this and other tasks in Course Site, please contact your Instructional Technologist by submitting a help request at https://www.lehigh.edu/help.