By Dominic Casciani
BBC News community affairs
The mere sight of a hooded teenager is enough to make some people hurriedly cross the road. But appearances can be deceptive. Not every street-wise youth is out to terrorise you. Meet Mr Hoody Two Shoes.
Sharmarke Hersi fits the description. He's tall with cropped hair and wears a hoodie and trainers. And for those whose fear of teenagers is driven by something more troubling still, the colour of his skin will no doubt make them cross the road.
But he's not happy about society's impression of him or his peers. In fact he's pretty angry about it - not least after he was stopped by police officers last year who were looking for a knife-wielding robber in north London.
When the A-level student asked why he had been stopped, he was told he fitted the description of a tall black man wearing a hoodie. If he meets the same officers again, he will be telling them that, subject to getting the grades, he's probably off to study international relations at university.
"It's like some kind of moral panic," he says philosophically. "I was on the train not long ago and a lady was holding her bag tight because of my dress code. You sometimes see people crossing the road to avoid you or putting their phone away."
Gang culture and youth crime is something that Sharmarke and his friends grew up seeing around their neck of Camden in north London.
Sharmarke Hersi: Tackled gangs, soon to tackle university
But after one student died in a knife attack in 1994, the head of one of the biggest schools in the area vowed to turn it around and instil in all his young charges a sense of community solidarity.
Huw Salisbury, now retired, was nationally recognised for his efforts at South Camden Community School, particularly because of his pioneering work in integrating refugee children into the mainstream. But Sharmarke says it's the former head's mantra of doing what is right for those around you that stuck with him.
"My little brother and his friends were hanging around in groups and had nothing to do. There was violence between the white community and the Asian community and people like me, Somali kids, were sort of in the middle. I didn't want to see them following in the footsteps of others, younger boys looking up to the older ones and thinking that gangs were the thing to do."
That's when youth charity Envision turned up. The organisation works with hundreds of teenagers, predominantly in London, and helps them take leading roles in shaping their communities. Unlike most volunteering organisations, it doesn't tell them what to do. Instead, it supports them in all their ideas - good and bad - and teaches them how to negotiate the roadblocks of officialdom which stand in the way.
In the case of Sharmarke, he wanted to set up a sports club, based around the martial arts he enjoys, to provide a focus and discipline for younger teenagers at risk of getting into gang culture.
Run on a shoe string budget, the project eventually attracted up to 40 people per session - 40 people who could very well have been hanging around on the streets. As a result, gang culture may be a little bit weaker today in one area of north London than it was two years ago.
"We believe that young people have the ideas and we want to take their ideas and turn them into action," says James Williams of Envision.
"You don't know what's going to work sometimes because every school or community is different. But it's about being willing to put some trust [as adults] in someone's ideas."
Demos, a thinktank that looks at what makes communities tick, says Sharmarke's experience and Envision's other projects have wider lessons.
Its new report looks into what makes Britain's most active volunteers. And it argues that fear of hoodie culture, and the branding of teenagers as apathetic or a threat, is damaging efforts to rebuild communities.
Crucially, argue authors Paul Skidmore and John Craig, society and officialdom's reluctance to listen misses a trick: if government wants to strengthen communities, then people like Sharmarke need the chance to do the work, rather than just be told what to do.
Banned: Hoodies barred from some shopping centres
Rather than focus on Asbo-aggro rhetoric, those in power should actually be asking the hoodie two-shoes in society for help in finding the way out.
The report's publication is timely. This month sees the first Children's Commissioner for England sit down at his desk. Professor Al Aynsley-Green argues that government needs to stop consulting young people and start properly involving them in society as citizens, albeit young ones. It's a view shared by Demos' John Craig who says the approach needs to be applied to volunteering.
"Young people expect to be able to engage and participate in communities on their own terms," says John Craig. "They don't want to sit on a committee and so on. Now that's a challenge for politics and politicians because some of the things that they may want to do are difficult to measure in terms of what they do for a community.
"But that's why we called this report Start with People because much more needs to be done to go to young people and challenge preconceptions that we may have.
"There's this desire [in Whitehall] to 'build capacity' into communities. I think that communities and people are pretty capable already and it's the politicians and policy makers who have to learn from them, not the other way around."