More than 120 NSW schools will be built or upgraded over the next four years with the state government injecting an extra $1.6 billion in Tuesday's budget to deliver on the commitment.
The government will spend $4.2 billion in total on the ambitious school building program which it estimates will create 32,000 more student places and 1500 new classrooms.
The Department of Education earlier this year predicted that by 2031, NSW would need 164,000 public school places in total to meet demand.
Funding will be rolled out quickly to address surging student numbers, Education Minister Rob Stokes says.
"We're going to see schools develop right across NSW but particularly where we see an increase in school-age population," he said on Monday.
Sixteen new schools will be built in Sydney growth areas alone, including Catherine Field, Marsden Park, Ryde, Penrith and Sydney Olympic Park.
Regional areas such as Warnervale and Tweed Heads will also benefit, while $747 million will go towards clearing school maintenance backlogs, including fixing toilet blocks and fencing.
As she spruiked her last pre-budget announcement on Monday, Premier Gladys Berejiklian was keen to highlight the 61 per cent rise in the state government's education spending.
"We have built on our education budget every single year, but nothing like you've seen today," she said.
"This investment is unprecedented".
Opposition Leader Luke Foley, however, argued the government was playing catch up.
"When it comes to school maintenance, and when it comes to the backlog of demountables, the task is huge because of six budgets in a row of cuts and neglect from the Liberals," he said on Monday.
NSW needs at least 7500 more classrooms, Mr Foley estimates.
"On the current trajectory, the Liberals are setting us up for increased class sizes," he said.
The education funding rounded out the final piece of Treasurer Dominic Perrottet's debut budget.
Nearly $1 billion has already been promised for hospital upgrades while roads and rail projects will continue receiving a significant chunk of the kitty.
The centrepiece housing affordability package will also include long-awaited stamp duty relief for first home buyers.
Mr Perrottet insisted there would be some surprises on Tuesday.
"We will see strong surpluses, the net worth of NSW continues to grow," he said.
© AAP 2017