Gradebook: Why can a perfect grade cause an average to drop?

If you have a gradebook on Edsby which has a large number of graded and weighted assessments, you may have noticed some peculiar behavior. Sometimes, when you give a student 100% for an assignment, this can actually cause their overall average to drop! Don’t panic, the gradebook and weighting form are working correctly.

Before a grade is entered for an assessment, its weighting value is not being calculated with the rest of the values in the gradebook. When the grade is entered, the new weighting is applied and all the values adjust accordingly. Grades which contributed more to the average earlier may contribute less once a new assessment is graded and cause their value and the overall average to drop. In these cases, you will notice that if you change the grade from 100% to 0%, the average still adjusts down accordingly. It is only when there is no grade at all and then a grade is entered that you may see the average drop.

This behaviour is confusing, but because grading is so complicated, it needs to work this way. You can always add more weight to the assessment so that its value actually contributes more to the average.

Here is a tutorial video which explains weighting in depth: