He took part in a mock press conference with Prime Minister Jacinda Ardern.
"It was a really cool experience getting to ask the prime minister a question."
While he cannot say what happened at the press conference, Gryffin says Ardern is nice and down to earth. She genuinely cared about the questions she was asked and is passionate about leading the country.
Gryffin says the media have a lot of freedom in New Zealand compared to some countries. The Government is open to journalists asking questions; politicians respect the media and vice versa. We are lucky to have this openness, as in some countries governments try to shut the media out.
Next year, Gryffin plans to go to the University of Otago and study science of some kind, possibly genetics. In Year 13 this year, he is taking English, statistics, biology, chemistry and physics.
The budding journalists were supported by Daniela Maoate-Cox, host of RNZ's The House programme. Gryffin learnt how to pitch and write an article, as well as conduct an interview.
He enjoyed getting to hear all the Youth MPs' stories and what they are doing for their communities. Gryffin had two articles published on RNZ's website, one on why youth should care about the local government elections and one about Youth MPs passing a mock bill to abolish the starting-out wage for young people.
Asked what he would say to young people about October's council elections, Gryffin says we should appreciate we have the right to vote in New Zealand, have fair elections, and have a good strong democracy. The council elections allow people to have a say in how the city where they live is run.
Gryffin got to talk to Maiki Sherman, chairwoman of the Press Gallery and TVNZ's deputy political editor.
Meanwhile, Gryffin came second in the Youth Parliament essay competition, winning $2000. Entrants had to choose from two topics: do you think Parliament has too much, too little or just the right amount of power, or, talk about an issue you are passionate about and how Parliament and business could work together to achieve change on this issue.
They were "pretty intense questions". He argued Parliament has the right amount of power, but citizens need to make sure they vote and engage with democracy to keep people accountable for the power they have.
He found it hard to form an argument on the "difficult topic" but says it was also an interesting exercise.
Gryffin is in his second year on the Palmerston North Youth Council. He works nine hours a week at a supermarket saving for university.
He says Palmerston North is a cool place to grow up with its multiculturalism, arts, music and theatre. For a smaller city, there is a lot to do.