The method Moodle uses to calculate your grade is different than the way you are probably used to from other classes you have taken. Moodle calculates your grades by using the number of points you earned over the number of points possible. As an example we will look at one of our courses. (The student we are looking at is a fictional student.)
The first point that we will look at is the overall average that appears on your Grades page.
If you average the above grades in the traditional way (add the grades up and divide by the number of grades), you will get that our student has an average of 71, not 31.56. The way the computer arrives at 31.56 is that it adds the number of points you have earned (represented by the actual percentage) and divides it by the number of points possible. In all courses, each lesson is worth 100 points. Our student has earned a total of 284 points so far. Since there are nine lessons, the total number of points possible is 900. The current grade is calculated by dividing 284 by 900 and multiplying by 100. This will give us 31.56%. As you complete more of your course this number will go up. It cannot go down because you are earning more points with each assignment you complete.
The second point we will look at is the Lesson Average. To view the assignments for each lesson, click on the lesson name on the Grades page.
If you were to calculate the average for this lesson in the traditional way (add the grades and divide by the number of assignments), the average would be a 92. However, that would be incorrect. Since each lesson is worth 100 points, each assignment is worth the same percentage of the entire lesson grade as the number of points it is worth. In other words, assignments are not all necessarily worth the same percentage. The number of points each assignment is worth can be found in the last set of parentheses. In this case the first assignment is worth 12 points or 12%, the second 16 points or 16%, and so on. To calculate the average grade for the lesson use the following model:
Percent(1)(Grade(1)) + Percent(2)(Grade(2)) + Percent(3)(Grade(3)) + ... + Percent(n)(Grade(n))
Remember that when multiplying percents, you need to either convert them to a decimal or a fraction first. For this lesson the average calculation would look like this:
0.12(100) + 0.16(62.5) + 0.04(100) + 0.04(100) + 0.24(100) + 0.4(90)
12 + 10 + 4 + 4 + 24 + 36
When following this method, we take into account the fact that not all the assignments are worth the same number of points. This is what is called a weighted average because each assignment is worth a certain percentage, or weight, of the whole grade.