With an international math competition ahead, a South Aiken High sophomore has redefined himself as a Stoner.

That’s a riff on David Stoner’s own quote a few years ago. Let’s put it this way: The 15-year-old has never worked on a math problem. He plays it with commitment and utter joy.

Stoner is headed to a prestigious math competition in Romania at the end of the month. His prodigious math skills are already well-known in Aiken. He won a regional MathCounts contest three years in a row during middle school, took first place twice at the state level and went on to the nationals.

A year ago, the Aiken County School Board recognized Stoner for attaining a perfect 800 math score on the SAT as a ninth-grader. Many other awards have come his way.

After a series of earlier competitions, a group of 50 students recently went through some more daunting tests. Stoner was one of 18 invited to move to the final preliminary round in Nebraska. Now, he and five other students throughout the nation have been chosen to represent the U.S. in the Romanian Master of Mathematics and Sciences in Bucharest.

They will participate in the math section individually, with their combined scores determining the international winner.

Stoner doesn’t know yet which students will join him, but got to know the other 17 participants in Nebraska.

“It’s great to have the opportunity to be with people of that same passion and interest,” Stoner said. “We’re motivated and challenge each other, talking about new problems we’ve seen.”

Jason Rodgers is Stoner’s computer science teacher this year and pre-calculus last year. Dorna Redd is Stoner’s calculus teacher for 2012-13.

“It’s amazing in terms of how David solves problems,” Rodgers said. “You definitely see something different in his eyes – almost an insight into the answer. You know he knows it, even finding the answer in a way you didn’t expect.”

David is the youngest son of Kevin and Karen Stoner, both of them engineers. He and his mother, who together relish math puzzles, are grateful to South Aiken faculty members for their support.

Rodgers has served as a proctor for some of Stoner’s tests to be returned to contest officials. The teacher had been prepared to do so again most recently, until competition administrators called and beckoned Stoner to Nebraska.

The challenges that he again will face during the Masters in Math event are focused on proof-based math.

“This particular test will consist of three problems in 4.5-hour slots for four days in a row,” said Karen Stoner. “It’s based on like knowing different theories and putting it all together as a flowing document. The answers can be six or seven pages each.”

David and the other students essentially will just become “isolated out there with no extra materials,” he said.

The tests can include number theory, functional equations and other high-level subjects that usually don’t get covered in the curriculum. As Stoner puts it, he spends much of the allotted time thinking.

“It’s a mixture of intuition and techniques,” Stoner said. “It’s really fun and that’s the reason I do it. There’s always an adventure to a new unknown.”