Students start turning up at school wearing matching purple shoelaces. Graffiti tags begin to appear on walls around the site. Unsavoury characters on BMXs start lurking around the school gates when the bell goes. Rumours abound that the school has a "gang problem".
All these worrying signs could prompt sleepless nights among headteachers: the stigma of being seen as a "gang school" could set the rolls falling and send the good teachers fleeing. Visions of a downward spiral ending in Ofsted failure and eventual closure haunt school leaders' nightmares.
But just how much do schools need to worry about gangs? Are they really penetrating the nation's schools? Are graffiti tags and playground brawls symptoms of an alarming problem - or just part and parcel of school life?
And if a school does identify a problem - either within its own walls or affecting pupils in the local community - what can it do? Are metal detectors and embedded policemen the right approach, or is it better to get children involved in thought-provoking drama workshops? Is it enough to stagger school closing times to protect children from the postcode wars on their way home?
More importantly, what can the school do to prevent young people from falling into gang membership in the first place?
Quantifying the problem
Various pieces of research have tried to quantify the problem of gang culture in schools, but few have come up with convincing evidence that it is widespread. Ofsted's Managing Challenging Behaviour report from 2005 found that gang culture was "perceived to be a problem in one in five secondary schools", but added that "few schools had evidence of it".
One in five of the 11,000 teenagers in the Safer London Youth Survey carried out in 2005 said that they would call the group of friends they hang around with "a gang" but less than 4 per cent were in a gang that had a name and a designated territory.
And academics who have studied gang culture at close quarters claim that much of the panic over perceived increases in gang culture in schools is overblown. Many gangs, they say, are friendship groups far removed from the organised criminal fraternities at the heart of the drugs trade.
Simon Hallsworth, gang expert and professor of social research at London Metropolitan University, says that youth gangs have become "a folk devil par excellence", being blamed for everything from last August's riots to school failure and dangerous dogs.
"Group violence is not a new problem in schools, it is part of our perennial history. There's always going to be a bunch of hard kids there saying, 'You're gonna get your head kicked in'," he says.
Government drives to tackle gangs are largely centred around London, Birmingham, Manchester and Liverpool; Nottingham is also recognised as having a problem. However, the rest of the country appears to be reasonably free from serious gang culture.
However, educators working in the heart of notorious gang areas are not as keen to downplay the problem. They have seen too many alienated young people failing to engage with school and being lured into the gangster life.
"People who say gang culture is not as bad as they say it is should come down to Hackney for the day," says Anna Cain, chief executive of the Boxing Academy, which works with pupils at risk of exclusion in the London boroughs of Haringey and Hackney.
Richard Brown, headteacher of the Urswick School in central Hackney, says that gang culture adversely affects the lives of many of his pupils outside the school gates.
Concerns over violence and intimidation mean that the school hosts its prom night on a Thames river boat, far from the local neighbourhood, for fear of gatecrashers and problems with security.
"It's a pretty sad thing that we can't host what is in effect a school disco," he says. "This school is a happy learning environment, a safe haven, but I won't pretend there are no problems for the kids once they leave the site."
The school uses weapon detection wands to search pupils when necessary and employs a "walkabout team" of support staff to ensure security at key times of day.
The role of schools
So, the problem certainly exists, and for some schools it is a daily challenge - even though the headlines can be exaggerated at times.
The current trend is to look to schools to solve many of the problems that teachers know are bound up in a complex web of social issues they cannot tackle on their own.
The final report of the Riots Communities and Victims Panel, which investigated the possible causes of the 2011 riots, called on schools to play a key role in preventing youth violence.
Published in March, After the Riots says that schools are failing to improve the "resilience" of their charges sufficiently, and suggests that schools "should assume responsibility for helping children build character" and introduce a "character test" in order to "help them realise their potential and to prevent them making poor decisions". How welcome such an initiative would be on the ground is uncertain.
The report also highlights the fact that many parents believe schools are not doing enough to tackle truancy - a key factor in young people becoming involved in gang activity. But schools are already inspected on attendance, and many will feel that there is not a great deal more they can do with the resources they have available.
So, amid all the headlines, the rhetoric and the blame, what can every school realistically do to broach the issue of group violence inside and outside school, whether it has already identified a risk or not?
Graham Robb, a former headteacher who now serves on the Youth Justice Board and leads the advisory group on education on the government's new Ending Gang and Youth Violence team, which emerged from a report on the subject last year, outlines a simple list of things every school can consider.
"First, you need to send a very strong message to all pupils that most children aren't in gangs, aren't carrying guns and aren't committing crime. It is important to establish positive social norms," he says.
Schools should also be wary of the offers they get from training and drama organisations to carry out anti-gang work. A whole industry has sprung up with consultants offering quick-fix interventions - often imported from the US - that may not have proved their worth. "Schools need to ask what the evidence base is for the work," Robb says.
He stresses that "shock tactics", such as schemes to take young people on tours of prisons, in the hope that it scares them off crime, have been shown to be ineffective. "Pupils need to engage with moral dilemmas, questions of values," he says, adding that all programmes need very careful preparation and follow-up work.
Schools do not exist as islands, and Robb stresses that they must keep on top of changes to the structures of other local agencies working with young people, as well as initiatives such as the new Troubled Families teams.
He points out that school site security should also be a concern: "Heads need to consider how a site would be managed by the police and school staff if there was a critical incident," he says.
School staff should also make themselves familiar with any court orders their pupils are subject to and the conditions of those orders. "Schools play a huge role in preventing reoffending," he says.
Forming links with local community, ethnic and faith groups is also essential for building the trust of parents, he adds.
Robb also recommends the use of confidential reporting systems such as Sharp - the School Help Advice Reporting Page (www.thesharpsystem.com).
Striking a balance
Once these things have been considered, a school has to decide what balance to strike between preventative, educational and enforcement approaches.
Clearly, a school with no identified gang problem is not going to install a metal detection archway, but it may wish to invite a drama troupe to provoke discussion among its students about responsible decision-making.
A 2009 report by the NASUWT teaching union, Gangs and Schools, highlights that enforcement techniques such as weapons searches can be used effectively. But it warns that schools need "to consider carefully their response to avoid placing those who carry weapons through fear at greater risk of exclusion and therefore involvement in gangs".
Hallsworth of London Metropolitan University has written about securitised school sites turning children into a "potentially criminal population" before any crime has been committed. Other leading researchers have also warned against excessive use of enforcement-led approaches.
Dr Jenny Parkes, senior lecturer in education, gender and international development at the University of London's Institute of Education, has interviewed young people living in troubled neighbourhoods about their attitudes to violence and gangs as part of the 2008-11 study Negotiating Danger, Risk and Safety: An Exploration with Young People in an Urban Neighbourhood.
"Gang culture spills into schools even with strong discipline systems," she says. "It's important for schools to look beyond zero tolerance."
In Merseyside - an area where gang problems hit the headlines in 2007 with the accidental shooting of 11-year-old Rhys Jones in Croxteth - police believe that they have helped schools to strike a balance.
The force has 34 schools officers stationed full- or part-time in 60 secondary schools under the Safer School Partnerships programme, which it has been running for the past eight years.
"Embedded" officers carry out a variety of tasks, from tracking down truants to delivering PSHE lessons on citizenship, responsibility and safety. They use everything from DVDs to restorative justice sessions to deliver key messages to students. But officers will also deal with flashpoints and incidents on site.
Inspector Colin Lewis, from the force's youth engagement unit, says that there is no longer any stigma attached to a school that has an officer on site, as there was in the early days. "Every school we work with describes their officers as invaluable," he says. "The only complaint I have now is: 'Why can't I have one?'"
Merseyside Police has also been proactive in its use of drama to reach pupils at schools in at-risk areas. In 2008, it commissioned a play, Terriers, and a supporting 10-week educational resource mapped against the key stage 3 English curriculum showing the consequences of becoming involved in gang culture.
Pupils are encouraged to explore moral dilemmas through creative writing, storyboards and monologues. Another version has been developed for use in primary schools, as the imperative to target children early increases. The Metropolitan Police has shown a strong interest in the project, bringing it to five gang-affected schools in London in March. And European funding could take the play as far afield as Marseilles in France, Gdansk in Poland and Cologne in Germany.
"Previously, police officers went into assemblies and told children not to get involved in guns and gangs, but this allows the young people to go on a journey and really think about the issues," says Detective Inspector Alison Foulkes, from the Matrix gun, gang and organised crime team at Merseyside Police.
But there may be even simpler methods to reach students at risk of falling into gang culture and crime. Experts on the front line say that many young people simply need to be listened to and have a key "parent figure" or mentor to nudge them on to the right track.
At the Boxing Academy, students at risk of dropping out are put in classes of just six, with a boxer as a mentor. "The main aim is to build a relationship with the young people. Then we get to work on their literacy and numeracy," says Cain.
But the key to the school's success is relatively simple: "We get massively involved with their lives, whether they like it or not," she says. Staff even go out to drag pupils into school if they fail to attend. "We turn up at their door and they are gobsmacked," she says.
- Leap: a social enterprise offering training and resources on conflict resolution. Its Working with Gangs and Young People course explores safety, territory, status, reputation and revenge. www.leapconfrontingconflict.org.uk
- XLP: a faith-based urban youth work charity, which works with more than 60 London schools to help children make the right choices and avoid gangs and crime. www.xlp.org.uk
- Chance UK: an early-intervention mentoring programme for 5- to 11-year-olds with behavioural difficulties. www.chanceuk.com
- NASUWT Gangs and Schools Toolkit: information from the teaching union on tackling all aspects of gangs and schools. www.nasuwt.org.ukInformationandAdviceProfessionalissuesBehaviourGangsToolkit
- The Home Office's November 2011 report Ending Gang and Youth Violence provides case studies and examples of best practice in schools. www.homeoffice.gov.ukpublicationscrimeending-gang-violence
THE POWER OF DRAMA
Many of the experts we spoke to agree that drama and role play can be vital in helping young people to think and talk about their feelings in relation to gangs and street violence.
And while the NASUWT teaching union warns that schools should be wary of the quality of the organisations offering programmes, there are good ones available.
The publicity for Bare Drama, a play exploring gang culture and prevention produced by Birmingham's Women and Theatre, says: "Young people can be sensitive to hectoring on 'issues' and are often resistant to work on subjects that are sensitive or exposing.
"Theatre provides a forum for them to explore complex situations."
Women and Theatre's projects coordinator Pippa Frith adds: "You can have discussions about issues very close to home through the creation of fictional characters. Pupils can project their own emotions on to characters without admitting they are having those feelings. It opens a dialogue and gives them a voice."
But she recognises the limitations of theatre: "Drama is never going to do everything on its own, there needs to be a lot of activities around training and education as well," she says.