If you only listened to anecdotal stuff about badly behaved children you might assume secondary school classrooms were running an educational variant on the Third World War.

But listen instead to a man like Stan Godek for an hour or so and you can re-locate your optimism gene.

Mr Godek has a batch of formal qualifications in psychology and neuroscience, but more importantly in the context of children with what the professionals delicately call "challenging behaviour", he has put in 25 years at the coal face. He has worked with children, their carers and teachers, tackling issues which cause them to act the way they do.

Last week in Society we reported on children whose behaviour and attainment levels had been badly affected as a result of never having had a secure attachment with the principal carer or carers, a crucial building block in forming healthy relationships and attitudes.

But what Mr Godek will be telling an audience of head teachers tomorrow is that no matter the age and stage of a child who is disruptive, their brain can be stimulated to react in more positive ways given the right conditions and exercises.

In his lecture on behalf of the TACT, the UK's largest fostering and adoption agency (formerly known as The Adolescent and Children's Trust), he will quote the distinguished American professor Phillip Shaver who contends that we can "rewire the neural legacy", and that children who carry the scars of past insecurity can be given "new mental circuitry and therefore the capacity to see the world differently".

In his work with children, Mr Godek has always known this instinctively and seen it in their progress, he says, but in the last six or seven years neuroscience has provided academic evidence to back up observation.

That marriage of relatively new science to long-standing common sense is important in that it validates the work being done when people like Mr Godek address sometimes sceptical folk grafting at the sharp end of education or fostering and adoption.

His contention is that when a child is involved in a violent or disruptive incident there will always be a trigger for it, even if that trigger is not apparent to the adult. "When a child is insecure they will impulsively react to perceived threat, even if that threat is only in their head.

"If they have never felt safe, then they will behave in certain ways, because their emotional brain is crowding out the cognitive side. We have to give that side space to grow and develop."

His shorthand for this is whether or not such children inhabit the green or the red zone. In the green zone they can rationalise a situation, they can think things through and stay calm. But on the cusp of red, or in that zone, their anger will be impulsive and easily aroused.

"The part of their brain which is the natural sorting office just isn't functioning properly because it has never been stimulated."

He's very clear, though, that while it is heartening that the brain has this neuroplasticity and can learn the empathy luckier children get from early attachment to a sympathetic adult and positive childhood experiences, the process of managing anger and gaining self awareness requires work and patience.

"There is no fairy dust to sprinkle here, but there is solid evidence that we can give these children that essential sense of security over time, and with that security comes the ability to trust."

The workshops and seminars he gives allow those caring for damaged children to understand a little more about those triggers which set off hostile reactions, and a little more about how to defuse them.

Analysis of the situation is pretty futile at the time of the incident, he says, given that a screaming child is not likely to be in listening or communicative mode. At that moment, understanding that the default position of a child with a malnourishing hinterland is fight or flight, you have to react in one of two ways, he counsels.

"Flight will need proximity, but fight needs space; you have to decide which is going to calm the child and the situation." And, as he points out, if the adult loses it as well, you basically have two screaming weans for the price of one.

However later, and more calmly, it's possible to sit down and analyse just what caused the eruption. It may have been nothing more apparently threatening than a teacher leaning over to point something out in the child's work. Entirely benign on the teacher's behalf, but awakening some fear from past experience of an adult in their close personal space.

He tells some very moving stories of working with children who have no positive memories at all of an adult who made them feel safe, so he tries instead to prompt recollection of a secure place in their life. With one small child it was a cardboard box in a coal cellar. So they installed one in the bedroom of his foster home.

But while our knowledge base expands as to how to mend small broken hearts, the number of children in need of nurture and nourishment of all kinds grows. He strongly advocates the introduction of secondary school nurture groups to mirror the primary variety, giving children food if they arrive hungry, and a nurturing, safe space at the start of the school day.

"And I worry, of course, about the number of foster carers who are encouraged to take in too many children with problems following the closure of residential homes. It means the children don't get the necessary time and space. And if that results in them fighting for attention it's not because they are attention seeking, it's because of a desperate need."

Where these placements break down, and rejection is piled on rejection, such children, says Mr Godek, have "a learned hopelessness" which makes them difficult to reach in a new family.

But if, on the other hand, you can find a way to win their trust, to let them believe in a better tomorrow, that is the first step towards turning a sullen, truculent, unhappy child into someone who can belatedly be given the priceless gifts of inner comfort and joy.