Randell is meticulous, transparent, and always one to have a voice. Known as "Boss" by his 240 staff members and "Grandad" or "Ran-Daddy" to his 2000 students, a series of tragedies in his earlier life fortified him. It also created a humility that's made him very likeable.
"[Loss] makes you realise life is not always a breeze. People do suffer and go through it, and it changes you. It makes you do things differently."
As a school principal you are both judge and jury, and it is a "lonely" job at times. To stand alone is to stand naked with your opinions.
"You're not always right and you've got to admit that too. And you won't always please people. I've tried to always live on a consensus basis, rather than having a vote."
He is a trusting person, particularly with the media, but knows when to keep it private.
"You have people come [to your office] and tell you such personal things and you can't really share it. When I was a young principal that was pretty tough. At school it was Mr Randell, at home it was Dad, Old Man, Pops. But it was very tough because you'd get home and you couldn't talk."
In the nearly two decades he's been at Otumoetai College, nine students have died. Randell has run the memorial service for each of them. As the boss, "somehow you've got to lead them through it".
He operates an open-door policy and likes to think teens can trust him. His own father, Gilbert, died in a road accident when he was in sixth form (Year 12) and he knows the roots of their occasional incivility.
"Having lost Dad, there are times I have youngsters in here that are bitter and twisted because mum and dad have separated, or dad is not there, and in a way, I can empathise with them."
That doesn't mean that he excuses their shenanigans.
He explains to teens, through his own life story, that "life is not on your plate".
He was raised in a state house and by age 10 was doing a paper run where a third of his wages went towards board. His family didn't have a car until he was 18.
There was an expectation he'd follow his dad into carpentry, but when Gilbert died age 44, he had a change of heart. The eldest of four children, he "picked up the reins" and supported his mother, Doreen.
"I was angry and I was determined to do something with my life."
The same year his father died, he came second in his class and put himself through university, working part-time in a garage and simultaneously obtaining a teaching scholarship.
He taught at Rotorua Lakes High School for 16 years before becoming principal of Taihape College for seven years and then moved on to Hamilton's Melville High School for five years.
In the first term, he had four students commit suicide, his first wife, Leonie, died from cancer and a teacher died of cancer.
As well as losing his dad and Leonie, Randell lost his sister, Kay, three days after he donated bone marrow to her in 2000. Kay died in Randell's arms. He also lost his niece, Nadine, to cancer and Jude, his second wife, had a brush with cancer when they married 20 years ago.
He and Jude both work long hours. Randell, a life member of the Secondary Principals Association of New Zealand (Spanz), works anywhere between 65 and 70 a week.
But there are several Randell rules at Otumoetai College. The number one Randell rule is you come first. Your family are second and work is third.
When travelling overseas on school trips, Jude, who owns Bethlehem Health and Tea Shop, comes too. It's not standard for principals to take their wives, but he views it as important.
Between them they have six children, 16 grandchildren and three great-grandchildren. Two of Randell's children were at one point his own head students.
"We have two Michaels, an Aaron and an Andrew, and Erin and a Keryn. So we have two boys at 40, two boys at 39 and two girls at 37.
"The expectations will be the Randell creche will be operating next year," he quips.
He has a collection of 2500 Matchbox cars at home and 300 fire engines. His retirement job will be to catalogue all his miniature cars, many of which live in the roof at the moment.
He also loves gardening at his property in Bethlehem. Roses are his favourite - he's got about 80.
At 69, he is ready to retire.
A couple of factors cemented his decision - he recently lost a close mate, the same age, from a sudden heart attack. And secondly: "I'm 69 when school finishes. Do I really want to be a principal at 70? It just sounds old.
"I think the school is in good heart and that's also why I want to leave. I want to leave with a legacy, rather than a vacancy."
The letters, emails and gifts have come flooding in since he handed in his resignation letter.
A bottle of wine from a 2004 Otumoetai graduate arrived on his desk the other day and with it a note. The former student turned winemaker wanted Randell to have his first ever bottle of pinot noir.
Further gifts: A Maori korowai, handcrafted by student Kane Anderson and his brother Moses. A rugby ball from the First XV. And then there's the letters … so many letters. Many of them are from what he calls his "delightfuls" apologising for their behaviour at school.
One letter Randell mentions is powerful in both its message and back-story.
In 2006, Eli Muller survived a fiery two-car crash in Bethlehem. His friend, Jordan Crockett, 17, died from his injuries and seven others were injured. Muller wrote to Randell saying he hadn't always been a perfect student, but with Randell's help, he is now in his final year of a doctor of philosophy in neuroscience and physics at the University of Sydney.
Muller wrote: "Your efforts over the years have had profound and long-lasting, positive effects. You have surely changed the lives of so many individuals and I consider myself one of them."
It moves Randell. He has been "blessed" with wonderful staff but it's the students who've made his job. "That's the rewarding part … It keeps you alive."
He believes the greatest challenge facing Kiwi teens today is our expectations of them.
This year he trusted his head girl and student executive to organise the school ball for 600 people, with a budget of $80,000.
"You've got to learn to trust young people and give them the guidelines. Getting young people to believe in themselves."
Education today is a new world with increased opportunities, but massive differentiations in demographics that challenge everyone.
He likes to be seen on the quad for a chat, and to pass on motivational quotes or affirmations - most of them Randell originals. He rattles off about six during our interview.
His most famous: "Success is not an option, it's an expectation, with that expectation must come that passion, that desire to excel.
"While we have the four values for our school, a lot of kids think this is my way, and that's the Randell way of doing it."
The Randell way extends to him rocking up to the annual Otumoetai College Peer Support and Leadership Camp in gym gear - a change from his 16 suits. A former gymnast, he devised an hour-long fitness test which he partakes in.
"I do press ups [with] claps and my feet come off the ground. And having done gymnastics, that kills everybody."
Taking centre stage on his office desk is a fat, lime-green ring-binder called The Manual. He's got a red folder for the man who will replace him, Russell Gordon, outgoing principal of Mount Maunganui College.
"It's everything you need to do in the first term, and I have a pink book: everything you need to do for the last term."
Short of frightening off Gordon, that's just how Randell is. Very organised. He's known for having the most groomed car in the school (he's a Ford man), something he gets grief over.
He insists he will let the school reinsgo completely, not slowly.
"I've just made a decision with myself that when I do leave, I have to leave. This is going to be Russell's school and yep, I'll miss it like blazes, but if I came in here, it would be at Russell's invite to come in here. In fairness to my new colleague, you've got to do that.
"Because I have been to places where the old guy keeps coming in and we don't need that."
Although he muses: "People tell me it's very strange, all of a sudden your opinion doesn't count!"
He is counting his lasts now … His last assembly, last prizegiving. "It's funny, that word 'last'. Where you don't ever have to do it again."
At life's crossroads, he's been known to say to students: "If I was standing behind you, would you make that same decision?"
Doing things the Randell way will be his longest-lasting legacy.