This article will be used by teachers who wish to understand why a student's grades are lowered after getting a high score on an assignment.
Grades are weighted by category. So if the score on the assignment is lower than the average for that category, the overall grade will go down.
Example: A student’s current overall grade is 90% for all categories (tests, homework, etc.) and they get a 92% on the next test, intuition tells us that their grade should go up. However, if their test average is 95% then the weighted average for the Tests category will go down and therefore their overall grade will go down as well.