## Mini guides for teachers

Under construction...

What is grade Aggregation?
The Aggregation method of a category determines how the grade is calculated:

• Mean of grades - Grade items are of equal weight
• Weighted mean of grades - Weights of grade items can be adjusted
• Simple weighted mean of grades - Weight of each grade item is its maximum grade less its minimum grade
• Median of grades - The middle grade (or average of middle two grades)
• Mode of grades - The grade that occurs the most frequently
• Natural - Maximum grade is the sum of the maximum grades of the grade items. Weights of grade items can be adjusted
Notes:
1. In the first three methods listed above, the category grade is a percentage
2. The Simple weighted mean of grades and Natural methods support Extra credit
3. The Natural method is somewhat non-intuitive when weights are used and the grades do not add up to 10 or 100.

As an example, suppose that there are four items in a category with maximum grades of 1, 2, 3 and 4, respectively.
Suppose the student scores the maximum grade in the first two items and zero in the last two.
His grade for the category is: