How do you get behaviour right? It depends on your character, the character of your pupils, the nature of your school and the nature of the incident. But there are common threads, ideas and solutions. In the Friday forum we’re asking you to share your experiences. We’re not telling you how to do it: you’re telling us how you’ve managed a particular child’s behaviour on a particular day. This week, a problem that took longer than a day to sort out: Belfast primary teacher Gary Trainor describes how he encouraged Mary, the child who didn’t fit in. Headteacher Mike Kent, LEA adviser Liz Henning, sixth-former Meg Shakesheff and psychiatrist Raj Persaud also comment. You can contribute to the discussion at www.tes.co.ukbehaviour

Corrosive relationships between pupils can spoil a class. Pupils like to feel part of a group, and if there’s one child who can’t or won’t play to group rules, if there’s one who becomes the butt of humour and ill-humour, classroom management can be sorely tested. For the 10-year-olds at St Kevin’s, a Roman Catholic primary on the Falls Road, Belfast, that butt was Mary, and Mary wasn’t helping matters. Class teacher Gary Trainor (pictured) had to face the fallout almost every day.

Mary was often late for school; she was overweight, truculent, unsmiling and uncooperative, and nobody ever wanted to be her partner, sit next to her or play with her at break time. She became the butt of jokes and name-calling and such playground discord would come back into the classroom on every occasion. Mary would complain about her peers’ behaviour towards her; they would always deny her allegations and Mr Trainor would have to disentangle the mess.

“She would constantly complain that so-and-so had taken her pencil, or pushed her, and it was no good saying to the others, ‘Did you take her pencil?’, ‘Did you push her?’ We were all getting bogged down with it. At first I tried to talk to Mary about it. I told her to ignore it, to walk away, but she didn’t respond. She had a leave-me-alone attitude, and we got nowhere. I tried talking to groups of pupils about it, but that didn’t work either.

“It was a quagmire, one of those repetitive discipline issues that is so frustrating. I would find myself talking to my wife about it, would find myself thinking, ‘Oh my God, what am I going to do now?’ on the way into school.

“When I asked children to work with partners I would hear them bickering about who was going to pair up with Mary. She would hear them too. It was cruel, and it bothered me to see a child so isolated. There were others in the class who were quiet and overweight, but they weren’t being picked on and isolated in the same way. It was as if her refusal to co-operate, to interact, to respond in any way, was attention-seeking, even if the attention was negative. She was forlorn; her whole body language said, ‘I am not happy’.

As a teacher with a no-nonsense approach to discipline, Mr Trainor was dismayed that his usual “firm but fair” method of managing pupil behaviour was making few inroads into this seemingly intractable problem. He tried talking to the girl’s mother, who confirmed that Mary didn’t mix with friends at home either, and who was also at a loss as to what to do about it. In the event, his realisation that he would have to adopt a very different approach coincided with a whole-school change in the culture of behaviour management.

Mr Trainor, 35, a Primary 6 teacher, has always regarded himself as direct and lively, but also as someone who leads from the front. “My approach was, ‘Right kids, come in, sit down, this is the way we are doing it’. I dealt with the issue, not the person. If a child had done something wrong, no matter whom, I would deal with it in a set way; there would be no room for manoeuvre.”

But, over time, Mr Trainor found his “black and white” approach to teaching was becoming increasingly ineffective, especially in an area where children were coming into school carrying the burden of significant social deprivation and with increasingly complex needs.

St Kevin’s draws from the Whiterock and St James districts of west Belfast, the city’s poorest wards, and former recruiting grounds of the IRA; drugs and crime rates are soaring and family cohesion is suffering. Half of the school’s pupils are on the special needs register and half are entitled to free school meals. The school itself, a maze of sprawling, crumbling brick extensions and boarded-up windows, looks like a building under siege. At times it has been.

When Mr Trainor started teaching at St Kevin’s, 10 years ago, there were more than 700 children in the school. Depopulation and falling birth rates have cut that number to just 480. But a new state-of-the-art school, which opened last month, has emerged beside it, evidence of the commitment from the Northern Ireland Assembly to reinvigorate the education system.

The headteacher, Kay McGuinness, was determined to fashion a building that would meet the needs of the wider community, and help to raise self-esteem.

She was also adamant that with a new school would come a new approach to teaching and learning. She introduced training to help staff and pupils move towards a positive behaviour policy; everything that happens in school, she says, has to be for the benefit of the children.

Mr Trainor has taken this to heart and believes this positive approach has helped him tackle pupils’ more complex behavioural problems and, in particular, to find a way to help Mary. “One of the things we’ve realised as a staff is that how well children learn depends on their interaction with their teacher. If you are intimidating, pupils tend to shut down, they don’t learn effectively. They still know where they cannot cross the line with me - the one kind of behaviour I cannot tolerate is disrespect - but I have shifted my line into their domain. I try to give them more credence for what they are and what they already know; for their feelings and aspirations. Before, I wouldn’t have wanted to know, but now I try to connect with what they are doing at home, their families, their interests.”

With Mary, he latched on to the fact that she was a good listener and could be astute. He began to praise her for it, and made sure other pupils heard him. Instead of making an issue of her being late every morning (for reasons he knew were outside her control), he let it go.

“Interrogating Mary about why she was late was always our first interaction of the day,” he says. “But as I began to see things from her point of view, I made little of it.”

He also introduced circle time, when “we could focus on bullying”. After a while Mary would be one of the first with her hand up to make a contribution. Again, he made a point of commending her. He also introduced “brain breaks”, carving up lessons with five-minute breathers involving fun activities. “I started to get the kids to do things like massage the shoulders of the person next to them, or make a human sculpture; Mary had to get involved, no question. She was reluctant at first, but a year down the line she was more accepting and accepted for being involved.

“I began to show more that I accepted her, and the other pupils followed my example. I began to see myself as a role model. I made a point of putting time aside to chat to each pupil each week, getting to know what they were up to, how they were feeling. I became aware that a positive comment to a child might be the only positive thing that had happened to them all week.

“It paid off, especially with Mary. Her manners improved and I praised her for it. She started being helpful and was one of the first to get our pupil of the week award. She began to take part regularly in PE, whereas before she would have ‘forgotten’ her clothes. She was still not the most popular girl in class, but she communicated. More importantly, she was no longer a catalyst for disruption.”

Mr Trainor says he has never been the kind of teacher to read up on behaviour management but admits that the whole-school focus on the issue has changed his entire philosophy. “Children are coming to school not knowing how to behave and you have to teach them, just as you need to teach them how to read and write. Whereas before we would have dealt with poor behaviour by sending a child to a senior teacher, or shouting, now we work on it creatively, through drama and music, through empathy and an emphasis on collaboration.

“I look closely at how children learn; not how I teach. That’s where I’m starting from.”

Friday magazine is offering every reader a free copy of Elaine Williams’s TESsurvival guide, Managing Behaviour (worth pound;2.99). Simply collect eight of the 10 tokens that will be printed in Friday throughout our series. Details of how to obtain your copy will appear in a few weeks’ time. You can find token 3 on page 3