Hi, @cschwarzrock , I wasn't able to replicate this. Specifically, I navigated to an ungraded discussion that had student responses and was able to edit it to change it to a graded discussion; when I did so, the SpeedGrader option popped up in the discussion menu. So for me, it worked as one would hope.
The only portion of the discussion that wasn't editable was in the group settings section (the message reads, "Students have already submitted to this discussion, so group settings cannot be changed"). This makes me wonder if the ungraded discussion was also a group discussion.
If that isn't the case, please ask Canvas Support to have a look at the discussion settings (How do I get help with Canvas as an instructor?: initiating the support request directly from the discussion in settings is best, because it will capture the metadata associated with the discussion/course/user and give the support agent good context).
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