Canvas calculates weighted grades using the overall percentage for an entire Assignment Group, not for each assignment score within a group. Thus, if there are varied point values in the Assignment Group, those with the higher point values will count more heavily on the student's grade. This could potentially throw off what you are trying to do with weighting.
If you have varied point values in a group using weighting and you want those assignments to all be counted equally towards a student's overall grade, you will need to "normalize" the assignments by creating new Assignment Groups for them and re-setting the weighted percentages.
1. In this example, the Tests group is counted for 60% of a student's grade, but each Test is worth different points. Thus, rather than being of equal weight, Test #3 will count more heavily than Test #1 and Test #2.
2. To "normalize" (make the tests of equal weight), a new Assignment Group must be added for each test with a different point value. The original weighted percentage needs to be evenly distributed amongst those new groups. In this example, the original 60% Test group is split into 3 groups worth 20% each.
3. After the new Assignment Groups have been created, click and drag the existing assignments into their new groups.
4. After all assignments have been moved to the newly split Assignment Groups, you can delete the original group since it is empty. The end result will look something like this, with one assignment per Assignment Group:
The effect on student grades will be immediate - go to your Grades tab to open the Gradebook and see changes.