The state budget has set aside $88.4 million in 2019-2020 to place a full-time psychologist and social worker in every NSW public high school.

Australian Psychological Society (APS) president Ros Knight said mental health issues affect nearly 1 in 7 children and young people between the ages of four and 17 years.

“Fifty per cent of lifelong mental health issues start before the age of 14 years, so school is the appropriate setting to catch early signs and provide early intervention,” Knight said.

A 2015 Australian Government report found that students with mental disorders have poorer NAPLAN results, worse attendance and don’t feel as connected to school or as engaged with school work as their peers.

By Year 9, students with mental disorders were found to be between 1.5 and 2.8 years behind their classmates, on average.

Knight said these findings highlight the importance of in-school psychologists.

“Evidence [shows] the link between mental health and student outcomes.  More psychologists in schools will mean children who need extra help will get it, and won’t be left behind,” she said.

NSW Premier Gladys Berejiklian announced the policy in February of this year, prior to the state election.

"It’s important for parents, for students, but also for principals and teachers to know the expertise is there," she said at the time, per The Sydney Morning Herald.

"It relieves the pressure, it gives students access to that extra level of support and the support can range from things like advice on careers, anxiety, stress, bullying and other issues."