The move is part of the government's determination to crack down on youth crime and will cost �10m.

By Katherine Sellgren BBC News Online education staff

For one London head teacher, the introduction of a police officer in his school means he can lock his bicycle away and put an end to his lunchtime patrol of the local area.

Five schools in areas of high street crime in Hackney have been assigned schools

Mark Emmerson, head teacher of Stoke Newington School - Media Arts College, was well known for his regular route around the surrounding neighbourhood in the London Borough of Hackney, just keeping an eye on pupils in their lunch break.

Before the arrival of a dedicated police constable this term, Mr Emmerson and members of his teaching staff regularly patrolled the school gates after some children were the victims of muggings on their way to and from school.

"We're a good school - heavily over-subscribed - in an area where there are elements of crime, often street crime, targeted at young people," says Mr Emmerson.

Mark Emmerson no longer needs to patrol on his bike

"We don't have problems we can't cope with in school, but we do have problems outside of school."

With a police officer on hand - with his own office - the head and his staff can concentrate on their real job.

"This scheme gives me some hours back to carry out my core responsibility - the children in the school - and it allows my teaching staff to get on with the job of teaching," says Mr Emmerson.

Building bridges

For the police force in Hackney, partnering schools is a chance to break down barriers among young people who may feel suspicious.

PC Sivaji on the girls' school beat

"We can promote a positive image of the police - we don't just go around arresting people, you can talk to us about issues, we are human beings," says PC Joy Sivaji, who is stationed at Haggerston Girls' School in Hackney.

Working within schools is also a chance to try and stop young people getting sucked into a life of crime.

In time, PC Sivaji hopes to set up a "surgery" in his office at the school where pupils can come and talk to him about issues which are bothering them.

In the meantime, he carries out truancy patrols in the surrounding housing estates and is at the school gates in the morning, at lunchtime and in the evening.

But PC Sivaji and his colleagues, who're based in five Hackney secondary schools situated in areas of high street crime, strictly do not patrol inside the school grounds.

Jock says the police give a sense of security

"We're not security guys, we're not in the school because it's a bad school, we're here to make sure it doesn't become a bad school," says PC Sivaji.

'Positive'

It's early days - PC Sivaji has only been in his school for a week - but he says "the vibe is positive".

And pupils at Stoke Newington School - Media Arts College generally back his view.

"It gives a good sense of security and gives an authority to the school," says 13-year-old Jock Norton.

"It's a good idea - if you're getting bullied out of school going to school, there's someone there to support to," says Jazz McIntosh-Brooks, 12.

Jazz says people now have someone to approach with problems

"I used to be really scared of the police when I was younger, now I feel like they are trying to do things for the good rather than just being on a power trip," says Ben Corlett, 12.

But another 12 year old, Hannah Maddison, says she has mixed views about the scheme.

"In some ways it's good because it gives extra protection for the kids.

"But also it gives the impression that the teachers don't really trust us enough just to have us and the teachers," says Hannah.

Mr Emmerson though is adamant that the scheme is simply about allowing teachers and school leaders to spend more time working to improve the children's education.

Hannah fears there could be a lack of trust

"It's not about what's happening in the school," says Mr Emmerson.

"A lot of heads up and down the country are dealing with issues that are criminal, and even peripheral to the school.

"They feel there's no easy access to local police, because of the pressure police are under, so having a dedicated police presence will be of great benefit."

The Hackney scheme is part of the Safer Schools Partnership introduced by the Home Office, the Department for Education and the Youth Justice Board in 100 schools in England.