Te reo is perfect for this.
As it's a language our children come across every day in school and in the community, it's an easier language for a New Zealand child to pick up than, say, Mandarin, which is far less familiar in our day-to-day life.
With those building blocks, it's easier to springboard to international languages.
When I was at intermediate school, I had a teacher who was fluent in te reo, and she would often pepper her speech with Maori words, giving me a familiarity with the language that has served me well in later life.
It made it far easier for me to learn Japanese at high school as the two languages share similarities like the "a ha ka ma" pronunciation and the rolled Rs.
Other countries require their young people to be fluent in more than one language.
According to the Pew Research Centre, almost every country in Europe requires students to learn a foreign language.
It's something I think is worth emulating in our neck of the woods.