Extra Credit Items are especially tricky in the Moodle gradebook, because their value can vary greatly depending upon where they are placed, what aggregation method is used, and the maximum point setting for the course total.
If there are no categories in the gradebook setup, the extra credit item's value will be added to the course total and calculated according to the aggregation method of the overall course category.
If an extra credit item is placed within a category in the gradebook setup, its value will be calculated within that category first, depending on the aggregation method for that category. The total of the sub-category will then be used in the calculation of the parent categories, according to their aggregation method.
Some aggregation methods (such as Simple Weighted Mean of Grades) will automatically set the course total to 100, no matter what the sum of all grade items. In that case the extra credit item points will count as extra percentage points (on a 100 point scale).
If you use the aggregation "Natural" method, the course total will automatically adjust to the sum of all credit items. In that case the point of the extra credit items will be added to the sub-category or course total points, which will be divided by the total points possible. For example if the total points possible is 500, then each extra credit point will equal .2 % of a final percentage point.
1. In your Moodle Course, click on the Menu icon in the upper left-hand corner of the screen to open the slide-out menu.
2. Click Gradebook Setup in the Administration block.
3. Click on Add grade item button at the bottom of the Gradebook Setup page.
4. Type a name for the item
5. Set the point value for the item in the Maximum grade box.
6. Click the checkbox to turn on the Extra credit option.
5. Click the Save changes button.
6. Extra credit items will be noted by a + icon symbol. In this case, 10 points of extra credit will be added to the final grade if a student earned all possible points.
Return to the Setup Gradebook main resource page for more information on other topics.