He dropped his degree and chased a career in education and never looked back.
Now, after 49 years in the profession, 44 of those at Bayfield High School, Mr Spence is retiring and will officially have his final day on Tuesday.
"The years have gone by very quickly," he said.
He started his career at Gore High School, now Māruawai College, in 1976.
After leaving that job he travelled overseas with his wife, travelling to Perth and Edinburgh where they took teaching jobs.
"We had actually not planned to be teaching but there was unemployment both in Perth and in Scotland and we were struggling to find jobs."
He returned to New Zealand in 1980, taking a role as a relieving teacher in the technical department of Bayfield High School.
"I’m so grateful.
"If you’re a teacher, it is a transferable skill right across countries."
Since then, he has taken on many different roles at the school.
He had been the assistant principal, head of the commerce and mathematics departments, a dean and the coach of many sports teams.
"I’m leaving, but I will probably still be involved in one or two voluntary clubs around the place.
"It’s a line in the sand."
Since 2015, he had taught mathematics part-time.
"I’ve loved it.
"When people sort of say that my day sounds busy, I say, no, it’s all self-inflicted fun."
One of the highlights of his career was his involvement with the school group Hope (Helping out people everywhere).
"Hope was the result of my Christian calling to look at how I could make values and community service more relevant to all students other than those who just share the same faith."
The group supported anything "community minded", he said.
It had been around in "one form or another" since 1981.
Retirement at the age of 70 seemed like a "good opportunity", he said.
"I’m enjoying disgustingly good health, so it’s a good time to put a mark in the sand when things are really going very well."
