The kids are alright: Why High Close is a very special school

The remarkable school gives society’s most vulnerable young people a rare chance to flourish

At first glance, Josh is a pretty average 14-year-old. He likes to play on the computer; he argues with his sister, Demi; his sentences have a tendency to trail off midway through. But after a minute or two it becomes clear that he isn't quite like other boys his age – and if you ever meet Josh he'll unabashadly tell you why.

When he was three, Josh was taken into care; the amount of adults who have come and gone in his short life makes for grim reading. By the age of six Josh had been moved 25 times, between relatives, friends, foster parents, carers – sometimes in one place for just one day. His birth mother had problems with drugs.

Without much coaxing Josh might also divulge that he is prone, in his own words, to "punch stuff and swear at people, proper," and that his increasingly aggressive behaviour not only resulted in his being excluded from mainstream school two years ago, but has threatened to harm his adopted mother Sue, who took him on when he was six: "You think a lot of love and a lot of attention will be enough," she says. "I don't think I realised how difficult it would be."

Since he left mainstream education two years ago Josh has been enrolled at High Close School in Wokingham, one of three schools run by the charity Barnardo's. It specialises in children with Educational Behavioural Difficulties, those who we used to call "problem children". There's a very wide spectrum of backgrounds, but it includes children in care or who have been adopted, kids who are victims of domestic abuse, and some, like the three students at High Close when I visit, who live at a children's home the rest of the time.

High Close will be 60 years old next year. In 1948 the original building was bought by Barnardo's in order to educate girls; since then the school has changed beyond all recognition. Now staff here care for 80 children from the age of seven to 18, around 30 of whom are weekly boarders living across four "units" – Cedars, Pinewood, Acacia and Willows – set in glorious green grounds near the main school. Each house has a living room, a kitchen and games room, with staff on hand at all times. The kids have a say in the décor, and so the walls are covered with pictures of Banksy stencils, group photos of grinning faces and tongues sticking out at the camera, and – delightfully – a huge poster of Freddie Mercury.

For the past year and a half, the 31-year-old film-maker James House has immersed himself in life at High Close for a new Channel 4 two-part documentary, Lost Children, which starts next week. The films follow the lives of the pupils as well as the countless teachers, key workers, residential workers and field social workers – the children to staff ratio here is an astounding one-to-one – who toil around-the-clock to support some of the country's most vulnerable young people. In Lost Children, the latest in a series of films about the lives of marginalised British kids by the young director, House focuses on two pupils, Josh and Courtney, in order to understand the circumstances that led them to this picturesque spot in Berkshire.

Eleven years after he was removed from his drug-addicted mother, Josh still sees his mum once a year. In a filmed conversation he tells House, "I always get worried every time I see her that she might be back on heroin and shit like that." While most of the boarders at High Close go home on weekends, the teenager has started staying on at High Close in order to protect Sue and his sister Demi from his outbursts. For Josh, certain behaviours we take for granted don't come easily; on his 15th birthday we're shown Sue giving her son a new PlayStation. He turns to House, not really knowing how to respond to his present. "How about 'thank you?'" his new friend suggests.

The relationship the pair developed during the 18 months that House spent at High Close, eating in the canteen, hanging out in the common rooms, going to lessons, had a profound effect on them both: "We spent two months just talking to these kids before even picking up a camera," House says. "At first it was like, 'but the place looks so lovely and these kids are so calm!' but then something happens andf you see how damaged they are… Soon you realise if these kids were anywhere else, they would be a nightmare."

It wasn't always a comfortable piece to make: "As a film-maker I kept having to think, what's his life been like, what's his behaviour been? What will happen to him next?" But as someone who quickly came to care about the child, House also had to think about how Josh would feel when he saw the film. For Josh, building trusting relationships is one of the biggest challenges in his life, so the friendship came with responsibility. In the end, seeing his own life and behaviour reflected back at him had a profound effect on the young person: "His first words when he saw the film were 'I was naughty, wasn't I?' He seemed quite shocked."

In any case, Josh was keen to see his story told. Deputy headteacher Jonathan Newport says, "He wants to be explained, to be understood. This became his way of explaining, of saying 'I've got a lot going on in my life, I'm not just a bad person' ". In many ways it was useful for him; as part of the process of coming to terms with the past, kids at High Close do 'life story work' with their key worker, looking at their past, their family and the factors that led them to be where they are now, in order to help them understand their own behaviour. The job of the staff, Newport says, is "to look past the behaviour to what is driving the behaviour."

In the case of Courtney, who was diagnosed with ADHD and emotional difficulties before moving to High Close at the age of 11, there was a lot more going on than first met the eye. It took a long time to realise that she could barely read because, as Jonathan explains, she hid the real problem – her fear at not being able to understand what was being taught in class – behind her outrageous behaviour.

The point of education at High Close is to give children emotional literacy as well as academic skills, but this environment isn't the right solution for every child. There comes a point in the film when Courtney's behaviour starts to plummet. As she herself puts it, "there is a little cell in my head that says 'I don't care'; it's like my head has changed" – and staff have to discuss with the 13-year-old and her family whether they can really help her. Nikita Burton, Courtney's key worker, says she worries about what life might be like for Courtney if she left the school: "When she's here she's protected. Once she leaves here it's out of our hands... If she leaves here what is going to happen to her?" Burton worries that she could fall through the net.

At the end of each school year, High Close sends around 15 teenagers into the outside world with, wherever possible, GCSEs – and certainly a new ability to relate to other children and adults. The day of my visit, I meet 14-year-old Antonio who is on his way to go strawberry picking, one of various after-school activities, including rescue-dog walking and sports. He is delightful, polite and charming, but he's also plagued by anxieties. Like many of the kids here, Antonio presents a complex picture, and fundamentally he needs a lot of care; if he wasn't here, he acknowledges, his life would be very different.

When it comes to talking about what drove him to a specialist school, Antonio looks at the table and shifts uncomfortably in his chair; then, with the reassurance of a staff member, he explains that when he joined three years ago, he'd just been excluded from his school in west London. Since then, he says, "I changed. Now I think more before I do, I don't get caught with the wrong crowd as much. Sometimes I still get into trouble, but... [at this school] if you're in trouble you know what you're in trouble for."

The key seems to be that staff at High Close listen to the young people, they give them space to express themselves so that it becomes possible to talk through feelings rather than keeping them inside. "Unless you help them take the lid off,"explains head teacher Zoe Lattimer, "the pressure cooker will burst. It is amazing," she adds, "how many young people go through their lives without anyone ever listening to them."

For the past three years Antonio has been a weekly boarder, going back to his f parents' house at weekends. Recently, in the light of a marked improvement in his attitude, he has been on a trial at a nearby mainstream school, just to see how things go. "It was good," he says with a shrug. "If I went to mainstream in Year Seven I think I wouldn't be able to… this was like a help to get me back on track."

Now he is a member of the student council, representing the young people in his unit in meetings, putting across any questions or suggestions they might have for the school. The pupils have a say in a lot of the decisions; even Lattimer, before she was appointed two years ago, had to sit in front of a panel of children. The overriding ethos is of being inclusive and giving these kids a voice while helping them to develop a sense of responsibility.

When Antonio leaves school altogether, he wants to "hopefully do something sporty, some sort of physical work." Exactly when he'll be fully re-integrated back into mainstream education isn't certain; but when he does, he says with a smile, "I'll be all right".

Each year 6,000 young people are excluded from British schools. The problem, says Jonathan Newport, who worked as a mainstream teacher for six years before joining High Close 16 years ago, is a lack of understanding. "Because of the level of complexity in many of these children's lives, it's difficult for the local authorities to know where to place them, and placements can end up being inappropriate." Different children need different care. When kids' needs are not properly addressed, he adds, "they can find themselves in a cycle of failure, and that is very dangerous".

Recently Newport has been asked to go into mainstream schools across the South East to look at ways of helping staff incorporate some of the techniques used at High Close. "You see these kids on the fringes in these schools and you can see how easily see they can become disaffected." Many young people with complex social needs, he says, are lost in mainstream schools, and things are likely to get worse.

"BBM, text messaging, all these things are changing the way that people communicate; it is so detached that kids don't develop the skills they need to maintain proper relationships." Whether we like it or not, we need to keep up.

"The educational system we have now," he adds, "is still the one set up for the industrial revolution." If kids aren't properly stimulated they're going to tune out: "So often, if a child is bored in class, the temptation is to stick a label on them, to medicate them. What they need is to be engaged, do something different. The system that exists now doesn't allow teachers to be imaginative".

The cost of sending a day-pupil to High Close is £41,000 a year (boarders cost much more) and the fee is paid by the local authority. This might sound like a lot of money, but it does include paying for speech and language therapists, psychotherapists, pastoral care and an army of support-workers who help deal with specific issues. As Lattimer points out: "These children are incredibly needy and it takes so much energy to look after their various needs. Our work is about providing an education for kids who otherwise would have fallen way behind, but it's also about keeping families together."

This means around-the-clock support for students and their guardians, and creating a home environment at the school with kids choosing their own meals, learning to look after themselves. Often it is the most basic social skills that these young people lack, like socialising and managing their emotions. As of this year, the cut-off age for High Close has been extended from 16 to 18 years – an often critical time, when children in care tend to fall between various services, finding themselves without the help they desperately need.

The final few months of a young person's time at High Close, Newport explains, are often the hardest: "That's when they test you again and again because they want to know what's going to happen next." There is a 100 per cent rate of High Close alumni moving on to college, apprenticeships or work placements. For up to six to nine months after young people leave, they have contact with their key workers and field social workers, but the point is that by the time they leave, they have learnt to stand on their own two feet.

Reflecting on his time at High Close, House says we've all got a part to play to in the future of our young people: "These aren't bad kids, these are just kids trying to find themselves in the world... trying to make decisions when the odds are stacked against them." It is our job, he says, "to understand what makes them who they are, and to convince these children that they are actually someone worth fighting for".

'Lost Children' is broadcast on Channel 4 on 31 July and 8 August at 10pm