Page Comparison

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Note that in this case "Joe" gets more of a boost from his 10 point extra credit item than Melody does, simply by virtue of having been excused from one item . . . this is logical, since 10/75 (0.133) is larger than 10/100 (0.100), but it may be unintuitive at first glance to some instructors.

In "Categories" mode, calculations are still point-based, and work along the same fundamental principle, though when it comes to extra credit there is a further complication. By organizing the points into categories, we end up with the idea of an item that contributes extra credit to that category specifically, where it doesn't make sense to determine the category contribution to the overall score unless at least one non-extra-credit item has been graded for that category.

• My Default Gradebook
  • Category 1
    • Item 1 (25 points)
    • Item 2 (25 points)
    • Item 3 (25 points)
    • Item 4 (25 points)
    • Extra Credit Item (10 points)

So under this case, we have the same basic calculation as above, but if we add a student who only completed the extra credit item, we get another non-intuitive case:

As you can see, it is not possible to calculate a 'category score', or in the case of this gradebook, a course grade, for Francis... s/he has received 10 extra points, but since P is zero, we get a division by zero exception.