Averages Can Be Mean

Over the last two years I've been exploring the problems and drawbacks of grading and assessment practices in school. One of the controversial elements of school, especially in high school, is the practice of assigning one number (a percentage) as a grade in a course. This number is typically an average of all the smaller percentage marks on assignments.

Using the average, or mean, of all the assignments doesn't necessarily tell an accurate story of what a student can do at the end of the course because it keeps remembering the early learning stages when the student's skills and marks were lower. A student who can consistently perform at a high level at the end of the semester, shouldn't be punished by the learning process early in the semester.

Mode can help tell a clearer story. Mode is the number that appears most often in a range of numbers. If a student begins the semester with C's and B's in a certain skill set, but over time masters that skill and regularly earns A's, mode would select A for a mark because it appears most often. Theoretically, this method would communicate a student's abilities more clearly. Of course, it is only one small part of helping improve communication.