A pupil at Invercargill's James Hargest College has been expelled after hacking into the school's computer system and accessing sensitive information about pupils and teachers.
The boy also got keys to the school, which has since spent thousands of dollars upgrading its security.
College board vice-chairman Neil Bramley told the Southland Times the board had expelled the senior campus pupil following a disciplinary hearing on August 19.
"In my experience it was the most serious breach of trust I have seen in a school ... he had access to very sensitive information about students and teachers."
The school had taken steps to ensure the same thing would not happen again, Mr Bramley said.
The boy told the newspaper it had been easy to get access to the information.
"It was a very personal system I managed to get into and lots of details of the students were in there." After viewing some details he had told other people about them, he said.
"There were guides on the system to show you how to do it ... I was the first one to get as far into the system."
He had access to a school computer after hours and had used it about twice a week for six months before getting caught, he said.
College associate principal Nadia Rose said the boy had been highly respected and trusted and she was saddened by his actions.
Pupils were not allowed to use the school computer system until they had signed a contract outlining the rules, she said. Balancing computer accessibility for pupils with keeping the systems secure was a difficult challenge for all schools, said Martin Cocker, executive director of independent cyber safety organisation Netsafe.
The boy's parents declined to comment.
