In Canvas you can give a student another attempt on a quiz, reopen a quiz, and give a student more time on a quiz by using the moderation tool.
Video Walk-Through:
https://player.vimeo.com/video/450231120
Step-by-Step Guide with Screenshots:
1) Open moderation for the quiz.
In Course Navigation, click Quizzes.
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Click the name of the quiz.
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Click Moderate This Quiz.
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View Moderate Quiz columns.
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The Moderate Quiz page displays the following information: