He is known as the "Human Calculator" and he has come to tell New Zealand children why the world of mathematics is much cooler than they think.
American Scott Flansburg, a best-selling author, holds world records for solving complex equations faster than they can be tapped into a calculator.
His achievements are recognised by the Guinness Book of Records, and he was given his nickname by US TV talkshow host Regis Philbin.
"My aim is for every child in the world to be able to count from zero to nine and to think like a calculator," Mr Flansburg said.
He wants to counter the idea that it is OK to be useless at maths. He believes innumeracy should be as unacceptable as illiteracy and says it is often parents who are to blame for letting children believe it is possible to get by without mathematics.
Touring 16 New Zealand schools this week, Mr Flansburg will teach classes how to count from zero to nine, rather than one to 10, and will unveil his secret of the number nine.
He hopes to get them so excited about the possibilities of mathematics that they will sign up to an online maths competition on his Mathletics.com website, which enables children to compete against students from all around the world.
The site is running a competition for NZ schools between August 24 and 31.
Mr Flansburg says he was 9 when he discovered his passion for number-crunching.
His teacher asked him to solve an equation on the blackboard, and he was able to do it in his head, without needing to write down any calculations.
After that, he would keep a running tally as his family shopped for groceries so his father could give the cashier a cheque for the right amount before the items had been rung on the till.