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How to cheat on a test using a desk
Write down some notes on a slip of paper.
Hide the notes in your desk.
This method only works if you sit at a desk that has a liftable top.
If you don't have this type of desk, you can try using your backpack in the same manner. During the test you can lift up your desktop and pretend that you're looking for something (like an eraser, or a pen).