This [trip] is a once in lifetime, I'm going to embrace it and consume a lot of caffeine, which is all part of the student experience anyway."
Mr Olsen has appeared in the Advocate numerous times over the past few years - he spent four years on the Whangarei District Council youth advisory group, is a youth ambassador for Unicef NZ, and has represented New Zealand as a youth delegate.
At 17 he helped set up a free healthcare clinic for youth in Whangarei.
He also works with the national youth advisory group, advising government departments and NGOs about issues ranging from mental health to education.
The Young Leader Awards recognised 60 young people from Commonwealth countries this year and included an 11-day residential programme.
The group will call on Twitter, the BBC and PricewaterhouseCoopers, among others.
There would also be meetings with senior government officials at 10 Downing Street, and the awards ceremony would be held at Buckingham Palace, where Mr Olsen will receive his award from the Queen.
Mr Olsen said he was feeling relatively relaxed about the royal encounter.
He planned to "suit up", naturally, but said he was usually comfortable "having a yarn" with anyone - a statement backed up by his proud mum, Helen Olsen.
"Obviously we're really proud of him, but this hasn't just happened. He's been working hard for a lot of years on a voluntary basis and I can vouch for that, because I dropped him off. It just seems like the more you give him the more he can do," Mrs Olsen said.
She said her son was an "exhausting" child.
"He was a speaker from way early. As much as we could talk and tell him, he would soak it in. From a little boy he could talk to anyone and everyone which is what we tried to teach him. So he's always had that knack."