What parts of a rubric are students able to see before and/or after completing an assignment? Can a rubric be posted that only be visible to those grading the assignment?
Anthony, if you add a rubric to an assignment students will be able to see the full rubric (all criteria, point value for different levels, etc) on the Assignment page - so if they click on the assignment they'll see the rubric. If you don't want them to see it before the assignment is turned in then you can wait to add the rubric until after the assignment has been submitted and closed to students. Yet, as soon as someone does add the rubric and start grading with it, it will be visible to students with grades and comments unless the assignment is muted.
I did a quick search in The specified item was not found. and found the following two ideas that seemed similar to what you are looking for - Allow a rubric to remain hidden until all students have received a grade for the assignment. & Hidden grades and marks from students. Both of these ideas are archived, but they might give you some ideas or additional information that might help.
If a traditional rubric is used to grade a Canvas assignment, students will be able to see all parts of it soon as it is added to the assignment. If it is a free-form rubric they will only be able to see the criterion and point values, until a grader fills in the free-form comments. If an assignment's grades are muted, they will NOT be able to see the completed rubric but can see the rubric criteria on the assignment page.
If you did not want students to see the rubric prior to then completing the assignment, you could wait until you are ready to grade the assignment (after the submission window has closed) then add the rubric to the assignment.
If you don't want them to see the rubric at all - EVER, then you really can't use a Canvas rubric, because once an assignment has student submissions and there is a rubric attached to it, there is no way to hide it from the students. You could however, delete the rubric immediately after you finish grading all the assignments with it and the scores would remain, but you would loose all of the rubric ratings and comments within the rubric.
I think that covers all the options you have in Canvas, but you could always use a tool outside of Canvas like a Google Sheet or something like that.
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