The Greens would spend $160 million dollars to make te reo Māori a core subject for all schools from years 1 to 10.
By 2030, there would be access to a senior te reo teacher for every 200 students at primary school, the party said.
The party made the announcement today at a hīkoi marking 45 years to the day since the Māori Language Petition was delivered to Parliament.
In 1972, activist group Ngā Tamatoa and the reo Māori Society presented 30,000 signatures calling on the government to introduce te reo Māori in schools.
Today around 50 whānau members honoured those involved, holding photographs taken from the original hīkoi.
They were called onto the steps of Parliament by Green Party MP Marama Davidson, whose father, Rawiri Paratene, was a member of Ngā Tamatoa.
She said making the announcement on the petition anniversary was special.
"We announced our support for te reo Māori to be taught in schools back in February, and we stand by that, but we now have a plan in place to show how we can achieve that goal."
The Green Party would double the number of scholarships available for people who wanted to teach te reo, she said.
To do this, the party would implement a targeted promotion campaign directed towards fluent and confident speakers of te reo.
Green Party Leader James Shaw said he could not wait for the day when all students in New Zealand's schools can speak te reo.
"I don't believe that we are ever going to have a truly multi-cultural country founded on a bi-cultural foundation until we understand each other's culture, and culture is contained in language."