"The physical part is easy - how to train, what to eat and there are nutritionists, dietitians and different coaches who advise you on how to keep your body in shape," Bunce said.
"But getting the real focus, the mindset ready for games is difficult.
"Once you separate yourself and quietly think about how you can perform consistently every week, it gives you heaps of confidence."
He acknowledged that the students he addressed would probably not remember him or have seen him play because they would have been toddlers when he hung up his boots.
Asked about the attributes needed to make it into the All Blacks, Bunce said drive, commitment and discipline and superior skills were important.
Year 13 student and Whangarei Boys' High School left wing David Nair said Bunceprovided timely advice on how to improve as a player game. He didn't really remember Bunce as a player but had heard that he had been amazing on the field.
Bunce has another engagement in Whangarei but that won't be until August 25 at a speaking engagement at Toll Stadium. In a TV chat show-style format, Bunce will share his most entertaining stories from his rugby career, his life after rugby and his thoughts on who will take home the Webb Ellis trophy with Sky commentator Scotty Stevenson.