More than 70 percent of teachers who participated in a te reo Māori teaching training programme say it supported their ability to apply tikanga and te reo Māori in educational settings.
An independent review into Te Ahu o te Reo found it contributes to the Crown's strategy of language revitalisation.
The government-commissioned report was made public on Monday, following the Minister of Education's announcement that funding for Te Ahu o te Reo had been cut by $30 million to fund new math resources.
Erica Stanford said Te Ahu o te Reo "is not a good use of taxpayer money" when New Zealand has a "crisis in mathematics."
"Half of our kids at age 14 to 15 are not able to pass a foundational maths test.
"We have got to turn that around, and as a Minister I have to wake up every day and make really tough calls."
"Te Ahu o te Reo supports Māori language revitalisation in a number of ways"- report
The Independent report, commissioned by the Ministry of Education, assessed Te Ahu o te Reo's success in alignment with the Crown's Māori Language Revitalisation strategy - which is called Maihi Karauna - and the strategy's three '"audacious goals".
One of the benchmarks set under Te Maihi Karauna included 85 percent of New Zealanders (or more) valuing te reo Māori as a key part of national identity by 2040.
According to the report: "Participants have reported an increased critical awareness and understanding of the importance and rightful place of te reo Māori both in education, and in the general fabric of society in Aotearoa."
There is also a vision by the Crown that one million New Zealanders (or more) will have the ability and confidence to kōrero in te reo Māori by 2040.
The report said, since its launch, Te Ahu o te Reo Māori had created about 30,000 language acquisition opportunities for the education workforce and whānau attached to learning settings throughout Aotearoa.
"However, in serving the education workforce and particularly teachers, the ripple effect of this investment should not be underestimated."
The report said the influence of teachers amplified the impact of Te Ahu o te Reo Māori on Māori language revitalisation "far beyond the obvious numbers of direct participants."
Survey data indicated in the report found more than half of participants were actively teaching, and "therefore regularly have the opportunity to both model and teach their Māori language learning to their own students."
"Consider the flow-on effect, when each teacher who participates in Te Ahu o te Reo Māori then teaches what they have learned to an average class size of 25 students per year. Then consider how that compounds when they also share their learning with their colleagues, as our data indicates they are," the report said.
"The potential overall contribution of Te Ahu o te Reo Māori to the goal of one million speakers increases exponentially."
The report also highlighted Te Ahu o te Reo was supporting the Crown's third "audacious goal" of having 150,000 Māori aged 15 and over use te reo Māori as much as English by 2040.
"It is clear that the education sector's contribution to the achievement of Goal 3 sits most squarely on the shoulders of the education workforce and whānau in kura Māori and Māori-medium settings.
"Their spaces are the seeding grounds of the most sophisticated and experienced bilinguals in Aotearoa."
Key Findings:
Another key observation outlined in the report is that Te Ahu o Te Reo Māori is experiencing "high demand," demonstrated by long waiting lists and exceeding regional programme allocations.
"This level of demand is a clear marker and direct result of the success of Te Ahu o te Reo Māori, highlighting both the obvious need and the enormous appetite for a programme of this nature in the education sector," the report said.
It found that English-medium schools "benefit the most" from the programme in its current form.
"Approximately 88 percent of all participants across all levels of Te Ahu o te Reo Māori have come from English-medium settings, where the primary language of instruction is English, indicating that they have been well served by the initiative to date."
Participants in all levels of Te Ahu o te Reo gained significant language progress, including improvements in pronunciation and confidence. Most felt prepared to move to higher levels, with 87 percent saying the programme helped reduce their fear of making mistakes, the report said.
"At the higher levels of the programme, 73 percent of participants surveyed said that the programme helped them to write accurately in te reo Māori, and 77 percent said it supported them to apply tikanga in educational contexts."
Feedback was "overwhelmingly positive", according to the report.
"97 percent of survey respondents indicated that they would readily recommend Te Ahu o te Reo Māori to others, and 79 percent said they were keen to take another Te Ahu o te Reo Māori course."
The report said their greatest strength was their "outstanding programme providers".
"Participants were nearly unanimous in their glowing reviews of providers and their programmes, with most noting the providers' outstanding skills in delivering engaging and effective learning opportunities."
The minister responds to the report
During a media standup at the New Zealand Post Primary Teachers' Association on Tuesday, Education Minister Erica Stanford backed her decision to reduce the funding and said the review could not provide evidence that Te Ahu o te Reo increased student achievement.
"What they did do was survey some teachers who said that it was nice, and it had an impact,"
Stanford said the report was qualitative data not quantitative data which is "really important."
"If you read the report, the quantitative data says that they couldn't see any impact on children's results, or they couldn't see that the outcome of the training was evident in the classroom."
"They couldn't measure that. It wasn't built into the contract unfortunately."