But a final headcount was not conducted before the class departed the trip, and his son’s absence went further unnoticed as the group returned to school.
“Everybody knows you do a headcount, and not just once, you do it when you pack up, and you do it when you unpack,” the father said.
Oxley said the alarm wasn’t raised until his son did not return home from school and his concerned mum called him.
The boy then confirmed he had been left behind, and it wasn’t until 3.35pm that the student managed to contact the school.
Oxley said his son was a “calm lad” and loved the school’s outdoor programme, but it was “outrageous” that the school was unaware of the absence until his son reached out.
“For everyone to get back in the vans and drive away without him, and nobody to mention it,” he said.
“It’s lucky that his mother was the first person to ring him, as she usually works without her cellphone until 6pm.
“Otherwise, how long would he have been out there without anybody noticing?”
He said it was also difficult to get through to the school to notify staff of the situation.
“When we called the school, there was no line to get through to anybody,” he said.
“It was all about pressing a button to get to a machine - there was nobody directly we could get in contact with.”
Oxley said once notified, the school acted quickly to locate the boy.
“They got their own group together, they got search and rescue out, they called the police,” he said.
“But it’s winter and at 3pm or 4pm the sun starts going down.
“He only had his jersey and mountain bike gloves, with no water and no lunch.”
Jason Reid, Kaiapoi High School principal, said staff maintained regular contact with the student and his family throughout the incident.
He said the student was provided with mobile data to use location tracking services.
“As a safeguard, the school also contacted emergency services to assist with the response,” Reid said.
Police sent the boy a mobile locate text, which, when responded to, gave the co-ordinates of the stranded teen.
This allowed the search party to find him.
This morning, the school met with the family for a review of the incident as part of the Education Outside the Classroom protocol.
After the meeting, the boy’s father said he was pleased the protocols were being reviewed, and he believed the school was taking the situation seriously.
“I don’t want any child to be left behind, so as long as everybody’s nice and safe, outdoor activities are great,” Oxley said.
The incident and its processes would also be reviewed with the assistance of the external agency, Education Outdoors New Zealand.
Kaiapoi High School said it was committed to implementing any additional safeguards that resulted from the review and would keep the school community informed about any findings.
Jazlyn Whales is a multimedia journalist based in the Christchurch newsroom.