At Strathcona Grammar, David Powell teaches the hard maths, but the equation that has some students distracted is the count down to the Rio Olympic Games.
"When they initially found out, they were a bit excited to have a teacher going to the Olympics - it's fairly big for them, but they bring me back to Earth," Powell said.
Away from the classroom, Powell is Australia's top male table tennis athlete, soon to make his Olympic debut. The 25-year-old earned his ticket with a first place finish at the Oceania Olympic Qualification Tournament last March.
"For me success was failing so many times and keeping on going," he said.
His Coach Mark Smythe said it was a failure four years ago that almost led Powell to quit the sport entirely.
"He missed out by one spot for the London Olympics, so to get over that negative experience and then to back up four years later to qualify, I was really happy for him to overcome that big hurdle," Smythe said.
And overcome he did, working his way up to the top of the Australian men's rankings. However Powell will still begin competition in Rio as the underdog. Chinese competitors have long dominated the sport, claiming 24 out of the 28 gold medals on offer since the sport debuted at the Olympic Games.
A factor that Powell said might help the Australian table tennis team cause some major headaches in Rio.
"They have so much pressure and stress on them to perform to win and they're expected to win whenever they play for us we're not expected to win anything," he said.
But the expectations of his year nine maths class may be a little higher. Come August, student Talana Kitchen is hoping her teacher takes some of his own advice.
"If I was to give Mr Powell any advice it would be to tell him what he told all of us at the start of the year, be persistent and resilient and you can achieve what ever you put your mind to," she said.
