Justin Bieber’s old sneaker is up for auction, with proceeds going towards building a new studio at his old school.

Bieber’s purple Nike sneaker may only be a size 7 1/2, but its earning potential is sizing up to be much bigger.

As of this morning, the highest of more than 100 eBay bidders vying for the right-side shoe – “with dirt and scuffs” as proof of authenticity – has offered $6000.

That’s sweet music to the ears of Kristin Frank, teacher at Stratford Northwestern alma mater, Bieber’s old school in Ontario, Canada.

“Certainly it has surpassed our expectations,” Frank said. “Anytime we can have the world watching what’s going on at Stratford Northwestern that’s fantastic.”

Frank says the school wanted to revamp its broadcasting and communications studio, but needed cash to pay for the expensive equipment involved.

Although Frank never taught pop prince Bieber, she fondly remembers him as a schoolboy.

“It was one of those moments where you got goosebumps because it wasn’t your typical high school student performance,” she said, recalling Beiber’s standout performance at a year-end school assembly. “He had something special.”

At a fundraiser brainstorming session, she says Bieber’s name inevitably arose.

“When we started looking at the technology we would need to grow our broadcasting and communications group we realized we’d have to raise lot of money,” she said. “The Justin Bieber idea came up and it certainly beat bake sales.”

Although she’s far from starstruck, Northwestern Secondary grade 11 student Abbie Chalmers is nevertheless excited by her brush with fame.

Clutching the coveted footwear, she told TV programme, Canada AM the saga has her fizzing.

“It’s not everyday where you get a superstar to send you something that he wore to raise money, so it was a mindblowing experience,” she said.

Even with the auction still in full swing, Frank says the fundraiser has already exceeded her expectations.

“We had a blueprint for what we wanted in the room and we’re still looking at ideas, but I think we’ll be able to buy the latest and greatest technology for this room.”

Anyone interested in hopping into Bieber’s shoe, has until Friday March 11 to put in a bid.

The shoe will be autographed and come with a letter of authenticity.

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