Their key criteria were that the destination had to be a developing country - they spent much of Year 12 geography comparing developed and developing countries - and they had to be able to help somehow.
They eventually settled on Cambodia where they will volunteer in schools and villages via an NGO called New Hope.
They will also visit the temples at Angkor Wat, cycle around the coastal city of Sihanoukville, check out a maritime park, and visit the Killing Fields and chilling memorials to the brutal Khmer Rouge era in the capital, Phnom Penh, as well as carrying out research towards their level 3 NCEA geography credits.
Briar Piercy, 17, said they wanted to experience another culture but also help their hosts in some way.
"So many people have helped us, especially the Jones family, it just seems appropriate to help over there."
Te Arahi Carrington, 18, said the appeal of Cambodia was its rich history and cuisine. Its people had endured unimaginable suffering in the 1970s, under the Khmer Rouge, yet retained their positivity.
"We've seen videos of people over there and though they aren't rich, they seem happy and appreciate what they have now, because of what happened 35 years ago."
While the Far North was considered poor by New Zealand standards, it was wealthy compared to Cambodia.
"An annual salary there is like pocket money here. We've got it so easy," she said.
Preparing for the trip had brought the students together and showed them how supportive their community was.
"This isn't a rich school but every family we approached donated something, even if it was just buying raffle tickets," Te Arahi said.
She hoped other academic groups would be encouraged to travel. She knew of plenty of sporting or cultural school trips but few academic ones.
Zayea Ruka, 17, said their trip showed students at low-decile schools could dream big.
"It's proof that you can do it. You don't have to have lots of money."
The group will be accompanied by a parent and teachers Esther van Dyke and Andrew Smith. They return on October 8.
Briar said they were grateful to their parents, school and everyone who had helped.
"It's going to be life-changing. I'm so excited," she said.