Kristen Schubert of Parachute told 9NEWS she wrote a letter to the singer and faxed his record label in New York asking him to be her date.
She did not get a response, but decided to take him anyway.
Kristen got a cardboard cutout of Bieber and the Grand Valley High School student took it with her to prom.
She says she took it to the dance and had professional pictures taken. She got lots of applause from everyone. When one of his new songs came on, a huge group came over and danced with Kristen and her cutout.
She says as a senior it was her last prom, and it was worth all the weird looks.
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