It was a routine argument, of the sort Geoff Harper* had with this particular boy almost every lesson. But for some reason, unknown to Mr Harper, this time it escalated. Within seconds he found himself eyeball- to-eyeball with the boy, or at least as much as you can be when you are over 6ft and he is 4ft 5in.

“He said to me, `I’m going to cut your fucking face; I’m going to stab you in the heart.’ I told him to go and stand outside,” Mr Harper recalls. “He was known for this sort of behaviour.”

There’s a good chance that the Year 9 boy in question is one of the so- called “one in 30”, the hard core responsible for a disproportionate share of disruption in schools. They are, in short, children whose moral compass is “unacceptably skewed”, according to Emma-Jane Cross, chief executive of Beatbullying, which conducted research into the extent of behavioural problems and came up with the statistic.

It’s a label that Mr Harper, a humanities teacher in South West England, recognises as accurate. “There is always a guy at the core of a riot, and if you take them out the riot dissipates,” he says. “Teaching is a bit like riot control, and there is always one kid at the centre.”

Ms Cross of Beatbullying claims these one in 30 are serial bullies, unable to control their anger, narcissistic and intolerant. They are often habitual truants and academic underachievers, and most have undiagnosed learning or mental health difficulties.

They are also almost invariably boys, says Gwynne Wilson-Brown, behaviour consultant and teacher trainer at Greenwich University. She says that often they are boys who have no positive male role-models, but it would be wrong to attribute their behaviour solely to coming from lone-parent families.

“They haven’t been loaded with the social skills they need,” she says. “They don’t know how to be angry and put it aside, they don’t have strategies for calming themselves down.”

She puts the figure at more than one in 30. In any class of 30, she says there will be 12 children who cause no problem, 10 who will co-operate because they like you, they’re afraid of you or there is a prospect of reward, six who are hard work but can be won round, and two who are almost unreachable.

“By the time they arrive at school they find it difficult to establish relationships, and it is their efforts to belong to the group that make them act out. If they are extroverts they can become very destructive,” she says.

One in 30 sounds about right to Tom Bennett, although he says it should come as no surprise that there are children who refuse to play by the rules. A minority of people insist on ignoring society’s rules, so why should schools be any different? And in many cases their problems are too intractable for schools to try to tackle alone.

“There will always be a tiny minority of pupils who are resistant to reform or regret,” says Mr Bennett, head of religious studies and philosophy at Raine’s Foundation School in east London and resident behavioural expert on The TES website. “The reasons are usually rooted so firmly in their formative years that a mere school can’t hope to deep-mine the damage that caused the scars in the first place.”

He says many of these children would be best served by the additional support available in special schools, but the policy of inclusion - educating children with special needs in mainstream schools - ends up disadvantaging both them and their classmates.

Teachers in mainstream schools don’t have the time to deal with constantly challenging pupils, or the training to help them overcome their traumas, and should not have to suffer the stress of trying to manage their behaviour, he says.

“We let these pupils down badly by insisting they attend mainstream schools,” he adds. “We fail them, and we fail the other 96 per cent who have their education damaged by the minority.”

John Bayley, however, is cautious about the concept behind the one in 30 figure. The former teacher, now a freelance adviser on pupil behaviour (www.jbayley.co.uk) and lead behaviour consultant for Education London, says it gives the impression there is somehow a magic-bullet solution to class disruption. “Quite often when you remove the most difficult child from the class another one takes their place,” he says.

But he does accept that difficult children share some characteristics, with the caveat that no two are exactly the same. They often have poor literacy and communication skills, and are often involved in power struggles, both with their peers and their teachers.

Linda Douglas* says her teaching experience has given her the ability to spot those pupils whose moral compass is skewed. “It is often plain to teachers who the maladjusted and sociopathic ones are,” she says.

She cites one boy who left her South Yorkshire secondary school this summer who displayed many of the characteristics of the one in 30. In one incident, he was part of a group that attacked a boy with special needs. Even when the victim was lying unconscious on the ground, this particular boy grabbed a wooden post and smashed his face just a little bit more. “He has shown no remorse and he even justified his actions,” says Mrs Douglas. “He is a mindless thug who gets off on gore.”

Mr Bennett recalls one pupil who arrived at secondary school with a statement of special needs for extreme emotional and behavioural problems. He had his own teaching assistant and differentiated work, but was still regularly excluded throughout Years 7, 8 and 9, usually for rude and aggressive behaviour. By the time he arrived in Mr Bennett’s class in Year 10 the pattern was well and truly set. “He terrorised me for a year,” Mr Bennett says. “He even turned his Lynx can into a flamethrower during a lesson.”

Eventually the boy was removed from school towards the end of Year 11, leaving with almost no qualifications. While a special school may have been able to meet his needs, inclusion ended up disadvantaging both him and his fellow pupils.

“Mainstream school offered nothing to him he wanted,” Mr Bennett says. “But the lives and education of hundreds of people were damaged because we failed to provide a suitable environment for him.”

Mr Bayley suggests teachers need to know how to deal with challenges to their authority and how to have a planned conference with a child about their behaviour. “I might say, `You think you want to be in charge in the classroom. I understand how you feel, and I expect you will be a great president when you grow up, but unfortunately I’m in charge now’.”

He says teachers can also remind difficult pupils that they are not going away, perhaps citing the number of times they will be seeing each other in class over the year to underline the fact. Other tactics include saying, “I’m a successful teacher and you are going to be a successful pupil,” a way of making it clear you care, and appealing to their sense of belonging by saying they are part of your class and should abide by the same rules as everyone else.

If these don’t get through, class teachers should gradually escalate their response, involving more senior members of staff. “Classically what happens is the pupil does something and gets a bollocking, but nobody listens when they’re being given a bollocking,” he says. “If your message isn’t getting through, don’t change the message, change the setting.”

Claire Lillis is also reluctant to embrace the idea of the one in 30 children. She believes it is an “unhelpful” label to pin on children. “It is very naive to think that if you remove the one very disruptive child that will somehow solve what is regarded as a problem,” she says.

Ms Lillis, headteacher at Ian Mikardo High, an east London school for boys with severe and complex social, emotional and behavioural difficulties, warns that labelling a child as bad can become a self-fulfilling prophecy, and suggests that disruption often involves more than just the one child at the centre.

“We can have an incident where a child seems completely unmanageable, is very aggressive and abusive, banging on windows, ripping down displays, not engaging with any of us, and we have to take him home,” she says. “But invariably there are other children who have been sitting quietly in the class who might be egging him on or looking to see what they can witness, and they are part of the dynamic.”

Her experience chimes with Mr Bayley’s: that if you remove the child seen as most disruptive, someone else will step up into the role. But she says that it is not always the most disruptive child who has the most intractable problems.

“There are some children who have experienced such early trauma that they find it difficult to relate to others. That child can be quiet - they’re not necessarily the child who is throwing chairs and being aggressive,” she says.

Where children have difficulty relating to their peers or teachers, even disruptive behaviour can be a positive form of communication. “Sometimes what we want is for them to act up, because at least they’re communicating,” she adds. “If a child lifts their hood and rips something off the wall at least we know they’re angry.”

Sometimes this goes too far, though. Melanie Reed* was plagued by a one boy in her Year 4 class throughout last year. “He was constantly spitting and swearing - dreadful swearing - disturbing the other children, calling me names, self-harming, hurting the other children,” says Mrs Reed, who teaches in west London. “I have 20 years’ experience so I know the difference between a challenging child and one who is out of control, and eventually I couldn’t handle it any more.”

The boy was given behaviour-improvement plans, time-outs to take him out of class, and fixed-term exclusions, but when he returned the problems started again. She says he was known for aggressive behaviour during the early years, but by the time he reached her class there were violent outbursts almost every day. “I knew we were on a collision course right back in September. The older he gets the bolder he gets,” she says.

Mrs Reed believes the emphasis on inclusion meant the school was reluctant to take the ultimate sanction of a permanent exclusion. But the consequence was that the education of the other children suffered.

“It was extremely upsetting for the rest of the class,” she says. “He would whisper to the other children to stop listening to me and it became really difficult to teach while all this was going on.”

A common approach, and one tried with this pupil, is the use of intensive sessions with behavioural experts. But Peter Keane is sceptical about the value of such work outside the classroom. While this can be effective with literacy, for example, he says it ignores the possibility that the classroom is one of the stress factors.

“There are very few children who don’t like the attention of a well- meaning adult, but put them back in the classroom and they will do the same thing again,” says Mr Keane, behaviour development officer for south Tyneside schools. “It is the context of 30 children in a classroom they can’t cope with, and that is what they need to learn to do.”

This seemed to the case with Mrs Reed’s pupil. “He would go into a room with a pupil support officer and be all sweetness and light, but when he came back into the classroom it started again,” she says. Intensive work with a team of support workers in the classroom also failed to work, however, as the boy complained he was being treated like a baby.

The strain of managing the situation eventually became too much and Mrs Reed was signed off sick with stress. Julian Stanley, chief executive of the Teacher Support Network, says it is crucial that teachers are given the support and information needed to cope with disruptive children.

“These children create a lot of difficulties for teachers, and where it affects the classroom it needs to be dealt with clearly and formally,” he says. “It is difficult for teachers in mainstream to manage disruptive pupils in a class of 30.”

Based on 20 years in teaching in both mainstream and special schools, Mr Keane says the “one in 30” figure is a fair assessment for the proportion of disruptive children. But he resists attempts to categorise them as a breed apart. Characteristics common to these children are ones we all share, he says.

“Disruptive children are not a different species. It might be more productive to look at the factors that put these characteristics in play.” These factors include life experiences, poor role models and a lack of effective strategies to deal with them.

Mr Keane works with challenging children in both primaries and secondaries. He is suspicious of attempts to try to “fix” children; instead his approach seeks to minimise the possibility that they will be disruptive.

“It’s no guarantee they won’t behave in that way, but the idea that there is something you can do to stop all disruptive behaviour is not very realistic,” he says. This work often involves building or repairing relationships with and between children, including setting short-term targets and rewards.

Although there are no sanctions and rewards at Ian Mikardo High, relationships are fundamental to improving pupil behaviour. “Conflict happens here all the time, from the minute you walk in the door there is conflict,” says Ms Lillis. “We spend a lot of time listening and talking to the child and getting the children to think about how they have made each other feel. It is about relationships, particularly the relationships they develop with their peers.”

Gwynne Wilson-Brown agrees that relationships with their peers are often the most crucial. She advocates techniques such as circles of friends, buddying and peer mentoring. Resolving problems with class conferences can give the whole class the responsibility for managing the situation, giving the rest of the class a stake in the positive behaviour of the habitual offender, she adds.

As much as 90 per cent of severe behaviour issues will naturally lessen over time, believes John Bayley. “If someone is telling you to fuck off, the chances are in 18 months they won’t be, without you doing anything,” he says.

“What most children are after is affirmation and respect from adults. It is one in 1,000 children who don’t want that, but being able to show you want that is a completely different thing.”

For the other 999 children, he says the key is developing a shorthand for getting your message across and finding a way to engage the child. “If you take a tough child on an outward bound trip and you hang off a cliff with them, you never have any problems with them again,” he says. The problem is, of course, that not every teacher has the time (or inclination) to hang off a cliff.

At Ian Mikardo, Ms Lillis says that teachers aim to create an ethos where every child is recognised for what they are and differences are celebrated. She acknowledges that some children, particularly those who have suffered early trauma, can be hard to work with and may need specialist therapy, but says their approach is effective for many children.

“Human relationships are so complex that I’m not sure any of us have the answers,” she says. “We’re human beings, things happen to us from the minute we’re born and they have a huge impact on who we are.” While there may not be any easy answers, it seems that as long as children have problems, teachers will have a role in trying to sort them out.

*Names have been changed

`I was the difficult child, so I became a teacher’

“I was a terrible attention-seeker when I was a child. I thought the world revolved around me. I wasn’t too bad at primary school, but when I got older I started to realise I didn’t fit in.

“I became a massive pain in the backside. I used to swear a lot and I’d always be arguing back. The teachers all thought I was a stupid idiot. I never did anything really bad - I would never have attacked a teacher - but I was just angry all the time.

“Ironically I ended up training to be a teacher because I thought I would be able to reach out to all the children other teachers couldn’t handle. When I was on the other side I realised I couldn’t deal with the disrespect and I couldn’t relate to these children. Often I hated them, just as I’m sure many of my teachers hated me.

“I’ve got an office job in west London now, but it’s only since I left teaching that I had the space to look at myself and realise what I must have been like at school.”

• Michael, 30

• Early Intervention

  The link between family background and behavioural problems has prompted one primary school to take a pre-emptive approach. St Oswald’s Primary in Bootle on Merseyside set up a register of children whose home situation made them more likely to have problems at school.

  Around two-thirds of the school’s 190 children are on the register, with issues including lone-parent families, family break-up, domestic violence and drug and alcohol abuse.

  Teachers and support staff are made aware of which children are considered particularly vulnerable, and can raise any issues they observe. The school then targets intervention based on the circumstances: from a call home or inviting the parent into school to calling in outside agencies.

  “Once you start writing down the children who have difficult backgrounds you begin to see a pattern,” says Leila Ford, pastoral leader at the school. “Children who have difficult home lives or their families are under stress tend also to have behavioural problems with special needs.”

  Around four out of 10 pupils on the school’s vulnerable children register also have special needs, but so far the pre-emptive strategy seems to be effective in preventing classroom disruption.

  “Right through the school there isn’t a child who is having an adverse impact on the learning in the classroom,” says Mrs Ford, special needs teacher of the year for north-west England in this year’s Teaching Awards. “Early intervention is really the key for us.”