Create an Assignment Group. 

If you want your course to automatically drop the lowest score, you must first create an assignment group.

1. Open Assignments
2. Select +Group. This will open the Add Assignment Group menu.
3. On the Add Assignment Group menu, enter the group's name and the percentage of the grade it accounts for.
4. Select Save.

For more detailed instructions, see How do I add an assignment group in a course? from Instructure Community.

Create rules for the assignment group

Next, you will need to create rules to specify what type of scores you would like to drop.

1. Find the assignment group where you would like to drop a grade
2. Select the menu button (three stacked dots) and choose Edit.
3. The group options menu will appear. Find the heading titled Number of scores to ignore for each student.
4. Enter the number of lowest scores you would like to ignore/drop.
5. Select Save, and the settings will be applied.

 For more detailed instructions, see How do I create rules for an assignment group? from Instructure Community.

If you would like to manually drop an assignment for a student, you must first set up an assignment group with rules, as described in the previous section. After this is done, you can choose a specific assignment to drop:

1. Open the Canvas gradebook
2. Locate the assignment in the gradebook. 
3. Scroll to the student whose score you would like to drop. 
4. Enter their score as 0 (zero).
5. The assignment graded as 0 will not be counted towards the final grade.

Notes:

• If the student has more than one assignment graded 0, only one will be dropped.
• If you would like more than one assignment to be dropped, you can specify this in the Assignment Group rules. 
• As a best practice, inform students why a zero is being entered if their assignment originally had a higher score.