As a teenager, Matthew Thomas should feel he has the world at his feet.

He is a quietly-spoken 15-year-old whose mind should be focused on his GCSE exams next year.

Yet at a time when most teenagers are beginning to step out from the protective shadow of their parents, Matthew hides away.

Bullying has reduced him to a painfully nervous, lonely boy with low self-esteem and a tendency to lash out at those he loves most.

He rarely ventures beyond the front door of the small Brighton semi he shares with brother George, nine, and mother, Ann, watching TV while his peers play outside.

As a lone parent, Ann, 49, says she feels helpless watching her son drift through what should be the best years of his life.

She said: "I sometimes sit and wonder what more I could do to help him.

"I try to bring him out of his shell, but nothing I do seems to help. The bullying has had such an impact on him he is afraid to go out and do all the normal things that kids do, like going to the cinema or football."

Yet Ann has gained hope through a scheme in Brighton which aims to boost youngsters' self-esteem by matching them with an adult mentor.

Matthew is on the waiting list of Fun In Action, a charity based in Edward Street which links youngsters with emotional difficulties with adult mentors.

The mentors agree to take their friend out to fun attractions on a regular basis during a minimum two-year period.

They have to be over 21 and be prepared to undergo a rigorous programme of police checks, training, and interviews before having their references taken up.

The scheme is modelled on the Big Brothers, Big Sisters scheme in the USA, which has mushroomed across all 50 states since being set up in 1904 and now links millions of children with adults.

Research showed 18 months after being matched, youngsters aged from ten to 14 were attending school more regularly, growing in confidence and getting along better with their families and peers.

Project manager Hilary Price said Brighton was well-suited to base such a scheme.

She said "We undertook a feasibility study which showed a high level of unemployment, many low income families and a large number of young offenders in impoverished circumstances.

"We got encouraging responses from social services, the crime prevention panel and the police who all told us to go for it. From that point we have gone from strength to strength."

There are currently 15 befrienders matched and a further 31 children on the waiting list.

Among the befrienders is Anne Simons, of Brighton, who draws on more than 30 years experience with children to act as a befriender to five-year-old George.

Classroom assistant Mrs Simons, 52, says: "I decided to get involved with the scheme because I genuinely believe every child deserves a chance in life no matter what their background.

"And it is very rewarding. George is full of beans, very intelligent and always very articulate. We go for walks, play games and do all the normal things children enjoy.

"I'm hoping the relationship which will continue beyond the two years."

The scheme has plenty of heavyweight backing. Its patrons include Tory peer Lord Skidelsky and former Brighton and Hove Council leader Lord Bassam along with education experts Dr Anthony Seldon and Patricia Metham.

Councillor Catherine Shelley, lead member for young people on Brighton and Hove Council, said befriending a young offender while she worked in social care was one of the most rewarding experiences of her life.

She said: "There is obviously a large number of youth schemes in Brighton and Hove but the difference with this is it is one to one.

"It is a really excellent scheme which is fully professional in who can and cannot get involved.

"From my experience, having a one to one is extremely valuable and I think it is something which can be replicated across the country."

"It is something I will not forget and I certainly urge others to become a part of."

Anyone interested in becoming a befriender can call Fun In Action on 01273 697734.