A vast painting of sea and sky, a whirl of yellows and greys, browns and greens is spread out on a long table. A group of Year 7 girls stare at it pensively, some standing on chairs for a better view. They have been working on this for weeks, each taking a different section, and are giving the result a critical appraisal. The discussion becomes heated. “I don’t think they’ve been looking properly,” says Shennel Gordon, aged 11. “That bit (pointing to a ship’s sail) should be lighter, more yellow, definitely not orange. They’ve just not been looking, sir!” “Okay, fair enough, you’ve made your point,” says Rebecca Chandler, 12, looking somewhat wounded.

Dave Latter, the genial but hard-working artist who has been guiding the girls through their work, looks satisfied as the brickbats fly. This show of passion from the girls proves, if nothing else, that they care. These 12 pupils at Waverley school for girls, an 850-strong 11-16 secondary in Southwark, south London, are classed as “vulnerable” - unable to cope well with school due to family break-up, dysfunction or learning difficulties. They are being supported through the transition between primary and secondary school in a special “nurture” class with a single teacher who can give them greater individual attention. Mr Latter is a resident artist with Dulwich Picture Gallery, which has worked with Waverley for the past two years, introducing this nurture group to its collections, and working with pupils on the art of looking, drawing and painting.

Waverley caters for a large number of recent immigrants and refugees. More than 50 languages are spoken in school, 60 per cent of pupils qualify for free school meals, 40 per cent speak English as an additional language and 30 per cent require learning support. There are security guards on the school gate keeping girls in and intruders out. It seems a world apart from the 19th-century grandeur of the gallery just 10 minutes drive away in its formal park, part of Dulwich Village, an oasis of privilege and wealth amid the prevailing poverty of the London borough of Southwark.

Dulwich Picture Gallery, built by Sir John Soane in 1811, is England’s oldest public art gallery, and has one of the country’s most important independent collections, with paintings by Rembrandt, Poussin, Claude Lorrain, Rubens, Canaletto, van Dyck and many other major works gracing its elegant walls. Traditionally, it has been an attraction for connoisseurs who would journey south of the Thames to enjoy the quiet and exclusivity of the collection. Yet over the past 16 years it has attracted many awards for the drive and innovation of its education programme, which has sought to make these fine Old Masters accessible to some of the poorest and most excluded members of society.

Last May, the gallery reopened after a two-year multi-million-pound refurbishment funded with lottery money, and now boasts the Sackler Centre for Arts Education, complete with lecture room and workshop with vistas of, and access to, the beautiful grounds. The gallery’s many education projects have one thing in common: the collection is their starting point. Gillian Wolfe, the gallery’s head of education and an award-winning author of art information books for children, says: “The children never say, ‘What has this 17th-century painting got to do with me?’ These are very good pictures, they have a universal quality that still speaks to us today. If you make it worth their while young people will look. The strength of the paintings means that they don’t go away thinking this is a fusty museum with fusty aristocratic paintings that have nothing to do with them.”

Over the past year, Dave Latter has taken his Waverley group into the gallery on many occasions. Recently, they made an enlarged copy of Ludolf Bakhuizen’s (1631-1708) “Boats in a Storm”, chosen by Mr Latter for its narrative quality and the opportunity for looking closely at colour composition within the dramatic sea and skyscapes. “It makes them question what’s in the picture, how it is made, what story lies behind it,” he says.

The girls appreciated working with an artist and his can-do approach. Nicole Smith, 12, says: “He shows us how to do things, but he lets us get on with it ourselves. We’re supposed to go home at 3.10pm, but I just want to stay and carry on every time.”

The work with Waverley school is part of the gallery’s Does Art Make a Difference? initiative, a pound;40,000 project funded by the Department for Education and Employment, now in its second year. Gallery artists have also been working with young offenders, including murderers and rapists, from Orchard Lodge Resource Centre, a secure children’s home for 11 to 16-year-olds with extreme behavioural and emotional problems. They have looked at the gallery’s Old Masters and recreated them in different, more contemporary styles. Clem Earle, 14-19 curriculum co-ordinator at Orchard Lodge, believes the project has played a part in the significant increase in entries for GCSE English and art this year.

A third institution that has a long-term relationship with Dulwich is Thurlow Park special school in West Norwood, London, for pupils with severe mental and physical disabilities. Gallery staff believe the partnerships give pupils much-needed security and stability.

Helen Dorfman, Waverley’s headteacher, is full of praise for the scheme and believes it is helping many of these vulnerable pupils integrate into the mainstream. Participants’ reading ability has also improved dramatically, she says, by as much as two or three years. “It gives an opportunity for these young people, who are from some of the most excluded groups in society, to build up a relationship with Dulwich Picture Gallery, and to realise that such a place can be for them as much as anybody else. I hope that confidence will stay with them,” she says.

As well as Does Art Make a Difference?, Dulwich runs art courses and a club for the long-term unemployed, and another major two-year outreach project called Art Icebreaker, which receives more than pound;80,000 from the Heritage Lottery Fund. Gallery artists and teachers take copies of Old Masters out into community institutions, such as the Bethlem Royal Hospital, Oaklands Refugee Services, and Wandsworth prison, devising innovative art projects based on them.

Incredibly, Dulwich has no education budget and has to seek outside funding for each project, yet it has built up an impressive education record. Gillian Wolfe MBE, the gallery’s head of education, began the work in 1985 as a secondary school teacher in Greenwich seconded from the former Inner London Education Authority. She wanted to show that the gallery, “in its quiet way”, had the potential to make radical relationships. “All human life is there in the collection,” she says. “Our job is to make that accessible. The staff here feel a missionary zeal about bringing people into this gallery. We only have one chance with some of these groups, and we want them to want to come back.”

Gellideg is an estate of 1950s utilitarian housing on the outskirts of Merthyr Tydfil, with panoramic views of the Valleys. When mining (coal and iron ore) and related industries died, the spirit, though not the pride, of the people of Gellideg went with it: they lost their work, but not their hope.

That hope lives on in Gellideg’s schools, and particularly its infant school, which has prompted usually restrained Ofsted inspectors to enthuse about “tangible moments of awe and wonder” as “teachers spontaneously ‘seize the moment’ to express joy at natural phenomena”. More prosaically, the school has also been praised for raising standards, and the key to its achievement is an emphasis on steeping the children in Welsh culture, music, narrative and myth, raising self-esteem through pride in their roots. But a focus on the visual arts and a celebration of the children’s own “mark-making” lies at the heart of the school’s efforts.

According to the Welsh National Assembly, one third of Merthyr’s working-age population is unemployed; Merthyr is one of the poorest areas in the EU, and more than 12 per cent of its housing stock is unfit; it has one of the highest teenage pregnancy rates in the EU. Yet, despite the deep social difficulties of the neighbourhood, this 140-pupil infant school is thriving. Six years ago it received a damning inspection report and a new headteacher, Branwyn Llewelyn Jones, who set out with her staff to make radical changes, one of which was to bring artists into Gellideg infants to do long-term work with children and staff.

After the next inspection four years later, the report was very different, described as “outstanding” by Merthyr Tydfil LEA. The school is alive with creativity, as pupils are encouraged to look, study and experience first-hand as much of the world around them as possible. In their many visits to explore their local region, pupils and teachers are always on the look-out for visual ideas. Children’s drawings of mythical beasts, of miners, of their local landscapes, are everywhere around the school, as well as pictures based on the work of Welsh artists.

Mrs Llewelyn Jones, a former senior lecturer in early-years education at Trinity College Carmarthen, has done extensive research into the role the visual arts can play in raising overall standards. Mark-making is a pre-verbal skill, she says, and if developed can encourage verbal expression and literacy. “Art is a language in its own right, a medium through which all children can express themselves if their efforts are valued. Through drawing, observation and making pictures they learn perseverance, they learn to think through their ideas, to listen better and to solve problems. If they experience things first-hand then their powers of expression will also improve.”

Artists Keith Bayliss and Tony Goble have been visiting Gellideg infants for the past three years. When I visit, Mr Goble, a narrative figurative painter and storyteller, a striking character with long beard and colourful braces, starts the day in assembly as Merlin, telling a Welsh Arthurian tale. Back in class, he and Keith Bayliss encourage Year 1 pupils to make drawings from the story they have heard. Some draw the wizard, others a hill with dragons underneath, confidently, obviously practised in mark-making. By the end of the day artists and children have devised large relief prints from the drawings which will form the basis for poetry and literary composition. Mrs Llewelyn Jones describes this as an apprenticeship approach, a long-term commitment in which children and teachers learn from the artists, and the artists in turn learn much about working with children from the teachers. Many of the children say they want to be artists when they grow up.

Mr Goble says: “By learning to look, the children are learning to see; learning to see means becoming conscious of the world around you and that way you become a better human being, as well as learning fundamental skills.”

Mrs Llewelyn Jones insists that children work with superior materials: the school invests in good paper, charcoal, Conte crayons and oil pastels, only using wax crayons for wax-resist projects. The pupils, she says, appreciate the materials they are given and repay the investment with good quality work. Last year, a Gellideg pupil, Kentan Jackson, then aged six, was a winner in Artworks, the first annual National Children’s Art Awards, impressing judges with his sensitive charcoal drawings of miners’ faces. The school put money from the award - pound;350 - towards creating a sensory garden. But children also achieve academically at Gellideg. The percentage achieving level 3 in key stage 1 SATs is 10 per cent above the national average. Mrs Llewelyn Jones says: “There is a close connection between creativity in art and writing at that level.”

The Clore Duffield Foundation, which sponsored last year’s art awards, is organising National Children’s Art Day on July 5. See www.art-works.org.uk for detailsFor more information about Dulwich Picture Gallery, tel 020 8693 5254 or visit www.dulwichpicturegallery.org.uk