What Are Weighted Categories?
For an example of Weighted Categories open "A Sample Class," and
choose "Weighted Categories" form the Grading Menu.
Notice several changes in the Summary window:
Points are no longer listed, because they have meaning only when
a weighting factor is applied.
The weight of each assignment category (that is, its contribution
toward a student's grade) is listed under its name.
Students' grades are not the same as they were under the unweighted
system.
Grades have been calculated as follows:
A student's percentage in each assignment category is multiplied
by the weight of that category and the results added to get a final
percentage.
Here is the calculation Class Action made for Watson Brown:
Category

Weight

X Percent

= Weighted Score

Homework 
.25 
75% 
18.75 
Classwork 
.25 
92%

23.0 
Tests 
.50 
64.3% 
32.15 
Sum 


73.9 
What Are Unweighted Points?
The unweighted or total point, grading system is the most common
grading system, probably because grades are easier to hand calculate.
Every point, whether it is in homework, essays, tests, or whatever,
is worth exactly the same as every other point.
Add up a student's points, divide by the total possible, and you
have his or her percentage.
Relative Merits of the Two
Systems
A major advantage of an unweighted or "point" system is that is familiar
to most students and teachers. In an unweighted system, "a point is
a point is a point," no matter whether it was earned doing homework
or taking a test.
Problems in unweighted grading systems can occur when the number
of points in an assignment area becomes disproportionate to its "value"
as an indicator of achievement. If you give more homework and fewer
tests than you planned, students' grades might be too greatly influenced
by their homework scores.
Such a situation cannot occur in a grading system using weighted
categories. If you decide that homework is to be worth 25% of your
students' grades then, no matter how much you assign, its contribution
will remain at 25%.
This is the major advantage of a weighted system. It allows you more
precise control.
The major disadvantage of weighted grading is that it can be a little
more difficult for students (and their parents to understand). If
you decide to use it, be sure you can hand calculate a grade (see
the example above). Somewhere along the way you will need to explain
your system to a skeptical student or parent.