Justin Bieber's got a new accolade to hang alongside all those awards and platinum records.

In a new interview with Australian paper The Telegraph, the "Boyfriend" singer, 18, reveals he's now also in possession of a high school diploma.

"I just finished high school," he tells the paper. "I passed my test--I'm free!"

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Adding that it was "hard" balancing his schoolwork with recording, promoting, and touring, the pop star says he stayed committed to finishing his degree for someone whose opinion he values most of all--mom Pattie Mallette.

"That was something my mom really wanted me to do, so I had to do it for her," Bieber explains--though he adds that, had it been solely up to him, he might not have finished.

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"This kind of lifestyle has given me a different perspective on life," he shares. "I've been able to travel the world. At school, usually you have to do a lot of writing and reading. I'm not really into that stuff. I like to be out there."

Bieber says his crazy schedule makes it hard to live like a normal teenager--but adds that he recognizes that it's helped him connect with his equally hard-working girlfriend, Selena Gomez.

"That's part of the reason we get on so well," he shares.

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Last fall, Bieber opened up to Us Weekly about trying to find creative ways to fit his schooling into his jam-packed schedule. "My mom lives with me, and then my tutor," he explained about his living situation. "Because I do school everyday so it just makes sense."

His favorite subject?

"American history," he told Us. "It is so much more interesting than the history we have in Canada!"

For exclusive photos, interviews and three giant foldout posters, order Us Weekly's special issue, Justin Bieber: Inside My World, today!

This article originally appeared on Usmagazine.com: Justin Bieber Graduates High School!