You've probably seen the increasingly popular matrix barcodes, "QR codes", used to sell just about any product, from magazines, to movies, to T-shirts.
But Mount Stromlo High School is using the versatile technology to sell students active ways of getting to school.
About 70 students have been riding and walking to school to search the streets for QR codes. If they spot one on the roof or wall of an underpass, they scan it onto their mobile phones and collect points that earn raffle tickets.
It's part of the It's Your Move program, through which ACT Health gave nine Canberra schools a $10,000 grant to find creative ways to improve student health.
Almost two thirds of Canberra's adults and about one in four children are overweight or obese.
Year eight student Noah Budd was this term's lucky raffle winner, scoring himself a $400 mountain bike.
"I wasn't expecting to win it and I was just glad that I didn't have to ride the bike on stage," he said.
"It's definitely nicer than my old bike."
While admitting the incentive of a prize boosted the appeal of riding to school every day, he said it's easy to stay active once it becomes routine.
"I think it's a great idea to encourage more students to get into the active process of riding and walking and encouraging them to do more sports," he said.
"Because it is an essential part of being a kid and of life."
Matthew Webbie, a Mount Stromlo teacher who helped create the idea, said the government's grant will allow the project to continue for a few years.
"The prizes won't last forever, but the main point of this was to curb the culture a bit so that students realise it's not such a big deal getting to school actively and that anyone can do it, particularly those who live close by," he said.
Teachers also urged students who live further away to catch a bus or a lift some of the way and walk or ride the rest.
Acting chief health officer, Andrew Pengilley, said ACT Health was impressed with the students' and teachers' innovative idea of linking mobile phones, scanning technology and health.
"I certainly wouldn't have thought of it," he joked.
"Some other schools have done work with nutrition by running cafes in school, another has looked at sun protection."
"So they've been quite entrepreneurial and diverse."