They carry big packs and wear special hiking boots.

This is a training session in preparation for a 96-kilometre trek through the Papua New Guinean jungle.

It won't be your average overseas jaunt. 

This group are one of the few under-18 groups to walk the Kokoda Trail - the area of southern PNG where Australian troops fought the Japanese during World War II. 

Over nearly two weeks they will tackle punishing terrain in intense humidity.

It will be a test of physical and mental endurance.

"I reckon I'll smash it," year 12 student Ella Roles said.

"I love challenging myself," she said.

Zac Holden, 18, is more measured.

"I expect it will be hard," he said.

Teacher Dan Hurrel said he expected the heat and humidity to be the hardest aspect.

The man to guide them on their journey is Andrew Flanagan. 

He's taken numerous Australian travellers along the trail before and is expecting the trip to be a life-changing experience for the students.

This is because he's seen what the experience did for his 14-year-old son Liam.

"He appreciates what it is to be an Australian, he appreciates how lucky he is and his self confidence has improved dramatically," Mr Flanagan said.

Mr Flanagan said these changes translated into healthier interaction with the family and a better attitude towards school.

The life-changing nature of the Kokoda Trail is also personal.

The father of six had been facing enormous pressure and anguish at home when, at the end of 2012, he took a trip alone through the region where more than 600 Australians died during the Second World War.

"My life was spiraling out of control," he said.

The challenging hike helped him process his troubles.

"You come back from this experience changed because you no longer believe that you can't get through anything," he said.

The experience put him on a new life course.

He became a professional Kokoda guide, got tattoos on both arms and perhaps most significantly, made the decision to change careers. He will soon take indefinite leave from his teaching position at Kangaroo Flat Primary School to be an education officer for the army. 

The tattoos encapsulate the values that have motivated Mr Flanagan since his first trek nearly two years ago.

The Southern Cross on his left arm is surrounded by four words: mateship, endurance, sacrifice and courage. 

"You come to realise these four qualities more than anything else because you experience them yourself," he said.

"They are the qualities we hold dear to us as Australians, borne out of Gallipoli I suppose, but even before that, the harshness of the Australian life meant that we were people who endured great hardship early on."

On his right arm the phrase "footsteps of the brave" is tattooed in capital letters. Explaining its significance makes him emotional.

He said when he walked along the track telling soldiers' stories it was like walking in their footsteps.

"I can feel Bruce Kingsbury (one of the fallen soldiers) at Isurava who won a Victoria Cross there," he said.

"I can feel Charlie McCallum who died at Brigade Hill." 

"There are times along the track when you're walking and it's very surreal," he said. 

"You can feel the spirits of the soldiers, I believe, and I've had other people tell me that."

Initially it was a passion for Australian military history that brought him to Kokoda, but something else happened while he was there.

He "fell in love" with the local Papuan people, who live in the small villages along the trail.

For him the trail is "sacred Australian ground" though the real owners of the land are the Papuans. 

Their ancestors were the Fuzzy Wuzzy Angels, the locals famous for bringing supplies to Australian soldiers fighting at the front and carrying the wounded to safety.

These days locals work as porters on Kokoda Trail tours.

Mr Flanagan said the people are selfless in the way they look after Australians unfamiliar with the environment.

"They are so welcoming and so generous with their time in what they're prepared to do for us," he said.

The Bendigo Senior Secondary students will spend time with locals halfway through the hike when they stay two nights in a village.

The villagers along the trail live an isolated, subsistence lifestyle so the students will bring medical and school supplies.

Teacher Dan Hurrel is interested to see how the students will engage with such a different culture.

"I'm sure it will shock me but I'm looking forward to learning about it, " student Zac Holden said.

Mr Flanagan said he hoped the trip would be the beginning of a long relationship betwee Bendigo Senior Secondary and the people of PNG. 

He said it was important people came back from the Kokoda Trail and shared their experiences with others so the sacrifice of Australian soldiers could live on.

He said it was a shame Australia's history at Kokoda was not taught more in schools.

Andrew Flanagan and the students leave for PNG next week. The Bendigo Advertiser will follow up on their experiences after their return.