In 14 November this year, five teenagers from south-east London stood in the dock at the Old Bailey to hear the foreman of a jury pass judgment on them. Helder “Mad H” Demorais, 17, Ricardo “Maggi” Giddings, 17, Jamal “J-Kid” Moore, 17, and Kyle “Clickz” Kinghorn, who turned 18 the previous day, were found guilty of murder and are today facing the very real possibility of a life sentence. Only Shaquille Haughton, 16, who promptly burst into tears, was cleared of murder. He was, however, convicted of manslaughter.

All five were members of the Guns and Shanks (GAS) gang and all five, the court found, had been actively involved in killing Zac Olumegbon, 15, outside Park Campus School in West Norwood, south London, in July last year.

Zac, who was a member of rival gang Trust No One (TN1) but had spent the previous day at a conference on youth violence, was stabbed to death as a group of teachers rushed, too late, to his aid. In the words of the crown prosecutor, Ed Brown QC: “Before he was able to start his school day he found himself hounded down and killed by these five defendants.”

This event, while horrifyingly memorable, was sadly not a one-off. It was not even major news outside the locality, which is perhaps unsurprising given the frequency with which teenagers are killed in the capital: 19 were murdered in 2010. It has become an undeniable truth in recent years that, for hundreds of thousands of pupils, avoiding becoming embroiled in street violence - either as a perpetrator or as a victim - is a daily struggle.

It was against this backdrop that, just a week before the Zac Olumegbon case reached its climax, a group of senior policemen, teachers, civil servants and even a surgeon met 90 volunteer pupils at London’s City Hall to discuss, for the first time, what could be done. The idea is that the children, who were self-selected from 20 secondaries, should advise police officers on coming up with new tactics to combat gang-related violence, and that this advice could lead to the Metropolitan Police changing the way it works with young people.

The scheme’s founders make clear that very little can be done to tackle this problem without learning from the children who face it on a day-to- day basis. Indeed, the vision takes this further. The Metropolitan Police has officially suggested that the scheme could lead to the creation of a “large group of influencers” who will go back to their schools and peer groups to promote ways to reduce harm.

Perhaps the most high-profile individual involved with this unique initiative is Barry Mizen, whose son Jimmy was killed in May 2008. Mr Mizen has since gone on to take a very public role in the battle against knife crime and street violence by setting up a campaigning organisation called Families United. He says he believes the initiative could stop future tragedies.

“Everyone was interested in the person who murdered my son after he was sentenced. Why were they not interested in the years leading up to that?” he says. “It’s easy for us as adults to think about what needs to be done, but we need to listen to young people and make them part of any decision. Then they will approach it willingly.

“For some children, the only chance they get to have access to a positive influence is while they are at school. The forum at City Hall is an opportunity for adults involved in tackling violence to hear the views and experiences of young people, especially those identified as leaders in their own peer groups.”

As such, the 90 Year 10s have been asked to produce plans outlining how to make their communities safer. At the City Hall meeting, these pupils heard from a prison governor, a police chief and, more surprisingly, a surgeon who became an expert in knife wounds after years operating on stabbing victims in South Africa.

The teenagers were able to question the panel about the impact of gangs and violence, and they will now work with their teachers and peers to come up with solutions.

The culmination of this work will come in the next couple of months, when the pupils will submit their action plans to police officers. The proof of the pudding, of course, will be in the eating. Will it actually change anything, specifically with local police? So far the signs are encouraging.

“We want to hear what the children are saying. I’m a white, 50-year-old man who doesn’t live where they do and I’m having to make decisions to deal with problems affecting their lives,” says south-east London area police commander David Zinzan. “This is an opportunity to listen to them. We want them to take back what they have heard to their schools, have debates in the classroom and then come back to us with a message that we haven’t thought of before.”

This is not, those behind the initiative claim, a one-off. In fact, they say that one day all London pupils will work with police in this way.

The scheme is part of the Safer Learners Partnership, a joint initiative from the Greater London Authority, the Metropolitan Police, the Youth Justice Board, the Association of Colleges and Transport for London. The partnership - chaired by Munira Mirza, the mayor’s adviser on youth and culture - was set up to help children who are experiencing threats and thefts on their journey to school. It is the first time all the organisations have worked together with teachers and pupils in this way.

Schools have been quick to sign up. One secondary head, Jane Willis of Nightingale Academy in Edmonton, north London, became involved with the partnership due to high levels of gang activity and youth crime in the area.

“The partnership put us in touch with agencies who had experience in the London region of priority issues and we took these ideas back to our local area,” she says. Another secondary head asked for help because female students felt threatened on their journey to school on public transport.

Already, there have been some results from the partnership. Transport for London’s Safer Transport Teams and the British Transport Police have agreed to shift patrol times on buses and tubes that pupils from another school said they felt “uncertain” on. In another area, there are now more police patrols near a pupil referral unit and school that reported regular thefts of mobile phones from children waiting at bus stops.

Certainly Nabeel Uddin, a Year 10 pupil and one of the 90 youngsters at the City Hall event, appears hopeful about what can be achieved. Nabeel, from Woolwich Polytechnic School for Boys in Thamesmead, south-east London, says the event gave him an “insight” into crime. “I also liked it as each person explained what they were going through and how they dealt with it. We learnt about sentences and how lives had changed.

“We are also going to hold workshops that train students in what to do if a friend or someone has been stabbed or shot.”

Breaking down barriers between the authorities and children would be a major step forward in itself - in many of the most deprived areas of inner-city England and Wales, positive collaboration with the police does not exactly have a long and proud history. So, if the pupils who are working to reduce trouble on the journey to and from school do make a difference it will be no small achievement. It might even go some way towards preventing more killings like that of Zac Olumegbon.

`ANGER AND FEAR’

Barry Mizen is the father of Jimmy Mizen, who was murdered in 2008 aged 16 after a row in a bakery shop. The case shocked the nation with its complete futility.

It made further headlines after Jake Fahri, 19, was convicted and Mr Mizen made an oft-quoted speech on the courtroom steps. “This country stands apart from most other countries in the world. It is a country of civility, fair play, fairness and safety. But we are rapidly losing that,” he told the crowd gathered there.

“We are becoming a country of anger, selfishness and fear. It doesn’t have to be like that. Let’s together try and stop it.”

Since the conviction, Mr Mizen has become prominent in the fight against street crime and was a founding member of Families United, a charity set up by families whose children have been killed. Also involved is Richard Taylor, the father of Damilola Taylor, who died from stab wounds in November 2000 at the age of 10.

Examples of the group’s work include the Count Me In: Together We Can Stop Knife Crime campaign.