The main concern is whether they will be able to fill the positions in time for a 2020 start, given the current shortage of teachers.
But Education Minister Chris Hipkins believes it will be do-able.
It was Ardern's first speech to a party conference as leader and Prime Minister. People queued around the block to get into the Town Hall but hundreds were turned away.
She said it was hard to describe the journey since becoming leader seven weeks before the last election but "frenetic, fascinating, fulfilling" came to mind.
She shared many letters she has received as Prime Minister, including one from an aunt of a boy with special needs.
It said: "We as a whānau have tried with dead ends wherever we turn so I then turn to you Prime Minister and plead for your help, he is missing out on so much and it just isn't fair. Please help us find a solution for this young boy who deserves the best chance living with autism."
Ardern: "So today I want to say to parents, to kids, to teachers, to aunties, to anyone who has asked for more support for those with additional needs – we've heard you."
Ardern also went somewhat on the defensive over two issues over which have been criticised by the Left - the Kiwibuild programme, which helps the middle class into home ownership, and the surpluses the Government is running.
On Kiwibuild she said it was helping thousands of young families into a home "not through a subsidy but the Government using our scale and buying power to do what the market hasn't".
And again aimed firmly at criticism by the Left, she quote what iconic Labour leader Michael Joseph Savage when state house tenants were moving into new home: "We are trying to cater for everyone ... we do not claim perfection, but we do claim a considerable advance on what has been done in the past."
She also defended the big surpluses saying it did not make sense to spend every cent you earned.
"The surplus is a safety net. Nobody knows what's around the corner. The surplus in an insurance against those risks."
Much of the conference was closed to the media, including a session dubbed Question Time in which delegates asked ministers questions, and another session featuring the Maori Caucus.
A small group of 1080 protesters chanted outside the conference but were not audible from inside.
It has been 30 years since a Labour conference was held in Dunedin. Cheese rolls, a southern classic, were served for afternoon tea.
Ardern spoke briefly on Friday night and then greeted her baby, Neve, in the foyer afterwards by putting a Labour-red knitted hat on her head.