Shutting down face-to-face learning, particularly in western Sydney, will cost NSW students more than $16 billion in future lifetime earnings, a new report has found.
Strict health orders coupled with curfews at the height of the pandemic adversely affected children in Blacktown, Canterbury-Bankstown and Fairfield local government areas.
The report commissioned by the NSW Council of Social Service calculated a collective loss of $3.1 billion from the "long-term impact of interrupted learning" in these three LGAs alone.
Addressing the Economic and Social Costs of the Pandemic and Natural Disasters also delved into unprecedented disruptions from bushfires and floods since 2020, finding an additional 13,400 children were at "risk of significant harm" between 2018-19 and 2020-21.
It estimated costs associated with child abuse and neglect ballooned to $7.8 billion.
Those who stopped school and remained disengaged were expected to lose $1.1 million in fiscal and social benefits over their lifetime.
NCOSS chief executive Joanna Quilty called on the NSW government to act immediately in the interest of children.
"Children have faced some of the greatest upheavals, with the closure of schools and early learning centres having a profound impact on their safety, social development and education," Ms Quilty said after the report's release on Friday.
"This report shows that children in western Sydney will be most affected - potentially losing billions of dollars in the course of their lifetimes due to lost educational opportunities".
But a "very concerned" Dominic Perrottet defended his government's handling of the health crisis including his push to open up schools when he became premier a year ago.
"As premier, I led the way in getting our kids back to the classroom as quickly as possible and we opened up our schools," the premier told reporters on Friday.
"Public health is incredibly important and so are other factors like mental health and educational outcomes of our children
"We put extra tutors into schools to help our kids catch up and extra counselling services. The long-term impacts on our kids were of deep concern to me during the entire pandemic."
Other evidence emerging from the report included a 36-per-cent increase in the number of contacts to the Kids Helpline.
The number of children presenting at emergency departments with mental health concerns increased 32 per cent - five times the previous annual growth rate.
Indigenous children were twice as likely as non-Indigenous children to start school developmentally vulnerable, while a 13-per-cent bump was recorded in the number of children from low socio-economic areas considered developmentally precarious at the start of school.
The report recommends the expansion of early intervention and child protection services, including growing the provision of culturally appropriate support for Indigenous and multicultural communities.
Another key recommendation was ongoing funding for an evidence-based, high-quality school tutoring program.
