Averaging student grades is an inaccurate way of measuring what they’ve achieved in class. At the end of the semester, do you add up all the points a student has earned throughout the term and then divide that number by the total amount of points possible to determine the student’s overall score? If you do, I encourage you to stop and adopt the practice of analyzing trends in student performance to determine their final G.P.A. First, let’s use an analogy to explain why averaging is a disservice to our students.
Pretend you’re a meteorologist charged with the task of reporting the average high temperature for 5 days in Traverse City during the spring term. On Monday you record a high of 59°, on Tuesday you record a high of 62°, on Wednesday a high of 63°, but on Thursday you drop the ball. You’re so busy with other obligations that you to forget to take the day’s high temperature. On Friday, you rebound strongly and record a high temperature of 65° – what do you do now?
Do you add in a zero for the high temperature on Thursday like a lot of instructors would for a missing assignment? If you did, the average high temperature for the week would be about 50° and undeniably inaccurate. In this instance, adding in the “killer zero” falsifies your records and the same thing happens in the instructor’s grade book. Fortunately, there is a better option for determining the average high temperature for the week.
Obviously, the temperature during this spring week was trending upward – the days got warmer as the week progressed. By analyzing the trend in weather, the meteorologist can safely say that Thursday was probably in the low 60s and the average high temperature for the week was probably in the low 60s too. Students are just like this meteorologist (they drop the ball, they have bad days, and they forget to turn in their work), but we, as instructors, can protect the sanctity of our grade books and even retain more students by avoiding the “killer zero” and analyzing trends in grades instead of averaging them together. A lot of my thoughts about this topic originated from Rick Wormeli’s Fair Isn’t Always Equal.