A Year 5 student attempted suicide due to stress caused by the NAPLAN test, a Canberra principal has told an inquiry.

Key points: Year 5 student attempted suicide several years ago on grounds of Canberra school, principal claimed

Year 5 student attempted suicide several years ago on grounds of Canberra school, principal claimed Principal spoke at inquiry into the efficiency and impact of standardised testing, including NAPLAN

Principal spoke at inquiry into the efficiency and impact of standardised testing, including NAPLAN Inquiry heard the child left halfway through test to try to take his life, after leaving note

Wanniassa School principal Shane Gorman said a teacher found the student attempting suicide on school grounds after walking out of class during a NAPLAN test several years ago.

"People don't realise the stress it puts on kids," Mr Gorman told an ACT inquiry into standardised testing.

The ACT Government established the inquiry into standardised testing to examine its effectiveness and how it affects the mental health of students as well as the morale of teachers, as part of a push to change how data from those tests is reported.

If you or someone you know needs help, call: Lifeline on 13 11 14

Lifeline on 13 11 14 Kids Helpline on 1800 551 800

Kids Helpline on 1800 551 800 MensLine Australia on 1300 789 978

MensLine Australia on 1300 789 978 Suicide Call Back Service on 1300 659 467

Mr Gorman said he was "likely to get emotional" retelling the incident, but revealed it to illustrate the effects of testing on students.

He noted the case was extreme, but also particularly alarming as he makes an effort to reduce the stress of NAPLAN testing on students and teachers.

"So in my school where I'm trying to create no stress about NAPLAN, that happened," he said.

"I hate to think what happens in other schools where it's high stakes."

The inquiry heard the child was a "well below-average" performing student with mental health issues, whose mother wanted him to take the test.

"She wanted to understand where he fits with everybody else. I actually tried to talk her out of doing the test, as we're not supposed to do," Mr Gorman said.

"I would lose my job over that."

Mr Gorman said the student walked out halfway through the test — leaving a note — and then went to take his own life.

"He was going to end it," Mr Gorman said.

Mr Gorman appeared alongside ACT secretary of the education union Glenn Fowler, who told the inquiry public reporting of NAPLAN data causes stress for students.

"If doctors said, in near unanimity, that a practice did more harm than good for their patients, would they be ignored for nine years?" Mr Fowler said.

"NAPLAN data should be removed from the My School website now and in perpetuity."

The Education Directorate has been contacted for comment.