The money is for "much-needed" infrastructure upgrades, including fixing classrooms and making them more modern, replacing roofing and guttering, and resurfacing paved areas.
While guidelines about how the money can be spent have not yet been released, Balmoral School principal Malcolm Milner called Ardern's announcement "a lovely surprise".
"It's good to see a government putting money into education, so the students will benefit from an improved environment," he said.
"It's a really nice and generous offer."
Balmoral School, which teaches year levels 1 to 8, will receive a one-off $400,000 boost.
Milner said the school has been caught out with leaky buildings, but 32 of its classrooms are currently being rebuilt.
"For us it would, of course, be about where the greatest need is and where the best bang for our buck is, so being really strategic about where we spend it.
"It's not often you get money like this."
He'd like to see the money spent on creating outdoor learning opportunities for the school's 880 pupils.
Ideas included a sandpit and a garden, where children could experience the tactile learning involved in growing fruits and vegetables.
"We know that learning is enhanced when students can use the outdoors too," he said.
The school might also look into some sustainability development, such as rainwater collection, Milner said.
"It will be good for the kids, it'll be great for them."
The funding package will benefit more than 2000 schools across the country .
