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We have a teacher that will give an assignment 12 points, but when looking at the assignment in performance, it only shows as 1 point. The number of points were not change after students started submitting assignment. Please see the screenshots below:
Assignment settings:
From Performance view:

Comments (3)
Hello Aaron,
Looking at the student information and it appears as if there was originally an auto-zero assigned due to the item being past the due date before the score was updated, which would have locked the activity into the older points possible. If you review the gradebook in the course any student that hasn't had an auto-zero assigned before the score change has the updated points possible.
That explains the cause of the issue, but how can we correct it?
The points possible will be locked in for that activity for the students that have already received a score at the previous points possible. The points possible can be updated via the API, however due to the weight setting it shouldn't be needed. The overall item weighting (the overall impact on the final grade) is the same when it is worth 1 point or 12 due to the weight being 100. You'll note that it has the section "Scaled to 100/100" which means that whatever the points possible it will be scaled to be out of 100 when calculating the final grade.