Tips for Calculating Grades

Tips for Calculating Grades




When using GradeBook for Google Sheets and Classroom you have a number of different ways to calculate the final mark for a student. 


Here are some of the most common methods: 




GradeBook Type:  Standard using a Weighted Average With this type of GradeBook all assignments are weighted relative to each other.  This is useful when you have a mixture of large and small assignments and don't want to worry about how many marks each are worth. 


Here is an example: Assignment 1:  25/30 Assignment 2:  10/20

In a total points system you would just average the marks:

(25 + 10) / (30 + 20 ) = 35/50 = 70%) 


However lets say you want Assignment 1 to be worth three times as much as assignment 2 then you would enter the following as weights in your GradeBook:


Assignment 1:  25/30       weight: 3 Assignment 2:  10/20       weight: 1


This calculation would be:

( (25/30)*3 + (10/20)*1 ) / (3 + 1) = ( (0.833)*3  + (0.5) ) / 4 = 3/4 = 75%

That's a 5% difference from a total points calculation!  The reason is because the student did better on assignment 1 and it is worth three times as much as assignment 2.


GradeBook Type:  Standard using a Total Points System This is a common system to use, just add up all the points and just average the marks.  To do this in GradeBook just enter the weights as the total marks such as:


Assignment 1:  25/30       weight: 30 Assignment 2:  15/20       weight: 20

GradeBook Type:  Category Based

With this type of GradeBook each category is assigned a weight of the total course and assignments within each category are weighted relative to each other.


A common category based system is:  10% Quizzes   30% Tests        30% Assignments 30% Exam


The sum of all the categories would make up 100% of the course. Now for each assessment you would assign a category and an assessment weight.  For the assessment weight you can use any of the methods mentioned earlier.


So in this system an assessment has a category to which is belongs (and the category has a weight of the total course) and a weight of how much it is worth within the category, compared to other assignments also in the category.


I hope this makes sense, tricky stuff!