Yummy pie pin-back button, looking good enough to eat – just don’t try putting this pie button in your piehole!
Not that we are recommending cheating in school, but you could make a math pin-back button with the answers to the test. We do, however, recommend making magnets to post that big F on the test when you do get caught! Make your own pi button or other math button, and hopefully you will have the information memorized in time for the test…. 3.14159….?