As a teacher, when you are assigning a test you have the option to click "Preview Test" to open it in a new tab and go through the test from a student's view. In this preview, you can go back and forth between questions even if you haven't answered them, by clicking on the "Previous Question" and "Next Question" buttons, shown here:

Its important to know that the "Previous Question" button will NOT show up on your students' view of the test. Once they've answered a question, they can't go back and change their answer. They can, however, disagree with a mark. Here's more information on what happens when they do that:

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