Te Ao Hou Te Kohanga Reo is so immersed in te reo that children did not hear their educator speak a word of English until she spoke to parents at the end of year production.
The Aramoho-based kohanga has wrapped up its year with 26 children performing the nativity play from start to finish in te reo in front of 100 family members.
The kohanga's head educator, Rene Pirikahu, said the evening was about celebrating the tamariki's development and acknowledging their families for entrusting the centre with their children.
"Everywhere in the world they focus their celebrations on Santa Claus which is great however, we are very strong in teaching our children and showing them and their families the purpose of celebrating Christmas which is the birth of Jesus Christ and they have a full and clear understanding of that," she said.
It was the first time a lot of parents and caregivers had heard their children perform in te reo Māori.
The evening was the only time the children and staff of the centre heard Pirikahu speak in English to address any of the parents and caregivers who were not immersed in the language.
"I pay large acknowledgement to the families because without them we wouldn't have the children and without the staff, I wouldn't have a team and we have a very strong team who are totally immersed."
Pirikahu said another highlight of the year was having a young Pakeha girl learn te reo.
Jessica Watson was referred to the kohanga reo by Pirikahu's mother last year.
"She came and offered her services as koha to the kohanga for helping her to learn te reo and spent two days a week with the kohanga for the whole year," Pirikahu said.
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"Her knowledge grew and became stronger and now she is totally immersed."
Watson shared her knowledge with family members of the children throughout the evening.
The evening also celebrated three children who were going on to kura kaupapa after leaving the kohanga reo.
Since 2014, 47 children have gone on to attend a kura kaupapa.
The kohanga reo first began in Whanganui in 1983 and has a roll of 35 pupils.