Banapa Avatea is already a role model as Huntly West Primary School's principal but he's now being hailed as a hero for his actions on the road last week.
Waikato police say Mr Avatea prevented a tragedy on a busy expressway.
Mr Avatea and his son Jordon, 5, were heading to school about 7am on Friday when Mr Avatea noticed the driver of a truck, carrying a digger, appeared to be asleep behind the wheel.
District Road Policing Manager Inspector Freda Grace said the truck was heading south towards Rangiriri on the Waikato Expressway.
Mr Avatea called 111 and described a truck travelling at low speed but causing massive damage to the barriers separating north and southbound traffic.
"The motorist (Mr Avatea) had tried to wake the driver by tooting but got no response," Mrs Grace said.
So Mr Avatea bravely got in behind the rear of the truck and activated his own hazard lights to act as a warning to following drivers.
Police said the truck veered off to the left and slowed right down, which is when Mr Avatea and another motorist managed to gain entry into the cab of the truck and apply the handbrake.
Mrs Grace said it was quickly established the truck driver wasn't asleep but was experiencing medical issues and an ambulance was called.
The Huntly West Primary School motto, "Kuhu mai ki te ako, haere ki te awhina - Enter to learn, go forth to serve", was going through Mr Avatea's mind as he went to the aid of the driver.
"I thought to myself, in among everything else that had happened, that's basically what we were doing, it's just making sure that when we're out there we're helping others."
When Mr Avatea approached the truck it was travelling very slowly.
But when it veered into the lane ropes and started to "really rip those apart", he realised there was something wrong.
"That was when I was able to get around the outside of the truck and have a look and saw that the driver was actually slumped over the wheel.
"That meant you had to act, you don't just leave that, nobody does. Anyone would have reacted the same."
Mr Avatea feared the driver had suffered a heart attack.
"(But) he wasn't holding his chest and he wasn't in pain, he was breathing and he was dazed.
"Then I looked in his bag and I saw he had a banana and a whole heap of chocolate covered museli bars, then I thought to myself, he's a diabetic.
"I asked him, are you a diabetic, and he was not really responding.
"So I got him a banana and pretty much shoved it in his mouth.
"It was just a matter of getting something into him."
Once the paramedic arrived, Mr Avatea carried on to work and got on with his day.
He said the word hero had been used a lot since the incident.
"If there was ever a chance to be a hero then I was a hero for my son and that's the beauty of it for my five-and-a-half-year-old, he got to be a part of something.
"While he doesn't understand it completely, he will be able to in years to come say that we were involved in that and we did it the right way.
"If we helped another person, which we did, then so be it.
"At the end of the day that's all you want to do is help other people and do the best you can."
Mrs Grace said police would now find an appropriate way of rewarding Mr Avatea and the other motorist.
"When you consider the risks posed to other motorists, let alone to the roading contractors working on the road works at Rangiriri, we could very easily have been dealing with a tragedy."
- Waikato Times