In an ancient Kintyre woodland, a group of teenagers are working among oak, birch, alder and hazel trees, while the adults accompanying them survey their activities with relaxed but watchful interest.
Now mid-way through a pilot forest school project, the carers' confidence in the ability of these special needs pupils from Campbeltown Grammar to handle themselves in this unfamiliar and potentially dangerous setting has grown greatly.
"At first, the carers were with the kids every move that they made," says Ross Preston, the course leader and Scottish Natural Heritage area officer, "but now they are happy to stand back and let them get on with it.
"They can see that the kids have learned how to use the tools properly and are becoming more independent. Right at the start we devised rules of behaviour for when we're out here."
The pupils' first job was deciding where to set the boundary of the forest school. Brightly coloured tape tied to trees around a little plateau now marks the chosen area. Supervised expeditions beyond, to find wood they could use to create a homely and comfortable space, presented the children with their first challenge.
"Pulling the trees up the hill was hard work," says Gillian, 16. "We did it two weeks ago. It was cold and wet then, not like today."
Forest schools, which are still embryonic in Scotland, though well established in England and Wales, take groups of children to selected woodland sites where they learn a range of practical skills, such as sawing, shaping wood, building shelters, making fires and cooking forest food. The groups visit the same site each week for a whole year in England and Wales (six weeks in the Scottish pilot), so they can become familiar with the rhythms of growth and change in the natural world. Even more important, and central to the forest schools ethos, is the growth that takes place in the children themselves.
"When you are responsible for them, it's not always easy to let these children think for themselves and take risks," says Deirdre MacPherson.
"But it is good for them.
"They do have to be carefully managed risks, however," says the development officer with Better Neighbourhood Services, a Kintyre initiative for children with additional needs. "So when Ross Preston approached us and Campbeltown Grammar with the idea of a forest school, the first task for all of us was to check out the site, the equipment and the activities and do a comprehensive risk assessment."
Training in the safe and correct use of saws, loppers and sharp knives is also vital, says Mr Preston. "Hey guys, how about a demonstration?"
As blue tits whistle in the trees above them and the wheezy song of a greenfinch carries up the slope in the still air, Stephen, 14, and Christopher, 13, demonstrate how a bow saw should be used to cut branches while keeping fingers out of harm's way.
"You put your arm through here to hold the wood, then you start sawing," says Stephen, using a technique that looks awkward but clearly works very effectively.
In no time, both lads have cut some wood for the hurdle, which directs the heat of the crackling fire towards the partially-built shelter, a framework of thin, flexible branches curved over and bound tightly together.
"We have also been learning how to tie knots, like a clove hitch and a Japanese knot for lashing things together," says Stephen.
"This morning we learned how to cut down a tree. First you make a notch in it, then you saw behind that, so the tree falls safely away from you and not on top of you."
Lewis, 13, explains that an appealing aspect of the project is that you "get to skip school". On a more positive note, the lad - now on his knees with others mixing mud at the behest of Mr Preston - says he was very keen to learn how to survive in the woods.
"What we're doing here is a wee experiment to find out the best natural materials for building things," explains Mr Preston.
The merits of soil and water alone, compared with soil, water and liberal handfuls of moss, leaves or grass will be tested by studying the effects of the weather on an upturned bucket of each when the group returns to the site for their next session.
"Am I as good as Ray Mears?" Mr Preston asks, comparing himself to the presenter of the BBC's World of Survival.
"Yes!" shout most of the children.
"No!" comes the voice of the class comedian.
While doubtless educational, getting right into a gloopy mess is, for some children, appealing in itself. Others are more fastidious.
"That's disgusting, Sam. You're not sitting next to me on the bus home. I think you should walk," says Charlie McLean, a special needs assistant at their school.
"Aw naw, sir. It's 35 miles."
While outdoor skills are valuable, the most important lesson the children are learning will stand them in good stead wherever they go, says Mr McLean.
"These kids all have different needs and at school they act very much as individuals. But when they came here they quickly began working as a team.
"Some of them will leave school with not very much. It is important for them to know there are people around who can support them as friends."
A couple of the children have greater needs than others, and cannot be left alone, says Sandra Harvey, a special needs assistant. "But they love to participate as much as they can and the others help to look out for them.
They think about keeping them safe."
Changes in the children's behaviour occur quickly in a forest school setting, says trainee leader Janie Steele, a ranger with the Forestry Commission. "My six-week pilot was with mainstream primary pupils who had dyslexia or behavioural problems. Different youngsters, but their confidence and social skills improved in the same way.
Like Scottish Natural Heritage, the Forestry Commission does a lot of educational work with children and teachers, says Ms Steele, typically through sessions on topics such as habitats or minibeasts. Even so, the forest schools training came as a revelation.
"We thought we would just learn a bit more about educating kids in the woods, never expecting this whole ethos that has changed the way we looked at learning. It was like Wow!" she says. "They explained about different learning styles - visual, auditory, kinaesthetic - which was new to me.
"The reason a lot of kids with behaviour problems don't do well sitting in a classroom is they need to be up and active. Bring them out here and get them doing things related to the curriculum and they get on really well.
"Forest schools have an amazing ability to make kids feel good about themselves."