When a teacher has yet to comment on a student's essay, the student is shown:

Incorrect

Marks for this submission: 0/6.

This shouldn't be shown at all because it isn't necessarily incorrect, it's just ungraded at the moment. This also shows up when the teacher goes to grade the questions-the teacher is shown the same statement.

There is an even more serious problem though related to this, and that involves the manual grading. The teacher is given the option of grading all student's answers to a particular question. However, if a teacher does not complete their grading of all student's answers for a particular question in a single sitting, and saves the ones they have done, if they go back to the page to continue grading, they are shown all the students over again, as if they were never graded at all, even if they continue to grade the ungraded ones, the grades for the others already done will be lost. It's an all or nothing situation. This is a fatal flaw for me as I plan to use this for a rolling enrollment course and I need to only grade newly submitted essay questions, not every one that was ever previously submitted.

It would be better if the Grade All option were actually a Grade Ungraded Essays option, and rather than consider the grade to be none by default, make it not yet graded. The fix for this would probably be to make Grade Ungraded Essays display only those essays that have 1 in the field graded in the table quiz_essay_states.