The week is called "kia kaha te reo Maori", or "let the language live".
Ardern said the language had survived "lots of ups and downs" but was now a living and thriving language.
"It goes without saying that te reo Maori is part of who we are as a country.
"I have an aspiration that my generation will be the last generation to regret not having the chance to learn te reo Maori in our learning and education journey."
She did not say whether she thought te reo Māori should be compulsory in schools.
"Even if that were a decision that were taken, we don't have the teaching workforce to actually be able to achieve it.
"So we've set goals around universal availability, that everyone who wants to learn can learn.'
She hoped the language would be spoken more and more informally as it became integrated into the education system.
Ardern also suggested that teaching New Zealand history in schools should be compulsory, adding that many New Zealanders would be surprised to learn it wasn't.
"It's not an unfair expectation. It's our history and we should learn it."
When asked, she cited the three articles of the Treaty of Waitangi, something she struggled to do at Waitangi this year.
"But I want to make sure that we're learning not just about te Tiriti, we're not just learning about the right of the Government to govern, the right of iwi to self-manage and govern, and for us all to be treated as equal citizens, as the three articles state, but ... the land wars, that we learn about regional history.
"What happened in the Waikato was different to what happened in the north."