Dawn arrives loudly in rural communities. In Gunjur, a Muslim fishing village in the Gambia, it’s not just the ear-splitting cockcrow that jolts people awake, the muezzin’s call to prayer is cannily magnified by a ruthless public address system that penetrates the furthest reaches of the village.

For Kathryn Tibbets, a geography co-ordinator at St George’s primary school in Swindon, this rude awakening is less of a shock than it would be for most of us. She is one of a group of teachers who are billeted in the west African village for a week, and her quarters are next to the local cinema.

She has spent a few sleepless nights listening to the menacing tread of footsteps, followed by sudden bursts of banshee howling. Although Gunjur has no running water or electricity, a municipal generator allows its residents to indulge a love of horror films.

The unexpected aural assault is just one of many surprises for the group, who are visiting Gunjur as part of a unique cross-cultural exchange which has linked the village with the town of Marlborough in Wiltshire for almost 20 years. During this time the Marlborough Brandt Group (MBG) has not only helped launch several development projects in Gunjur, from health education to women’s literacy and small loans schemes but, most importantly, it has given people from both communities the chance to immerse themselves in each other’s cultures by travelling to each other’s countries and living alongside a family in their home.

Kathryn’s group represents a fairly broad band of the profession - a primary and secondary head, humanities and geography teachers, primary teachers and a teacher trainer. Each has paid just over pound;500 for the trip, organised by MBG’s education arm - the Wiltshire World Studies Centre.

Before leaving home, the teachers each identified a clear educational objective they wanted to achieve from the visit - a team of four from Tregoze primary in Swindon wants to compile a video diary to use in school assemblies; Pam Stoate, the deputy head of Hardenhuish comprehensive in Chippenham, plans to establish a link between a Gambian school and her own; Geoff Anderson, a lecturer at Westminster College, Oxford, is accumulating a pictorial day book called Globe V, in which children from all over the world contribute drawings and personal recollections about their lives.

Sam Woodhouse, who has just left Marlborough Brandt after nine years as education director, put the programme together. She kept it deliberately loose to allow the teachers to join in fully with the life of their host families, such as negotiating the colourful mayhem of the local market, cooking, or joining the women in the fields, cultivating vegetables.

Gunjur is a bustling community of sandy avenues and ramshackle family compounds shaded by orange and mango trees. It lies a couple of hours’ drive from Gambia’s capital, Banjul - which is as far as most tourists get.

Although a white face causes less of a hoohah than it used to, it’s still enough to stop local people in their tracks and elicit screams and laughter from the many children who shriek “twobab” - “whiteface” - at us at every turn. The people of Gunjur have embraced the Marlborough link with a generosity and hospitality that is humbling. Although most families are just scraping a living, they think nothing about “adopting” the strangers from Wiltshire. As a result, pupils in schools throughout the county have teachers who know at first hand what it’s like to have to haul the daily water supply out of a well.

Host families give each visitor an African name. Within seconds this becomes known by some invisible bush telegraph and we are hailed wherever we go by our new identities. Everyone seems to know where we are going and who we are going to see, and it is not uncommon to be suddenly waylaid by a gaggle of shy children telling you to stop what you are doing and come home because supper is ready.

My host is Maryatou Darboe, whose compound includes her own family, plus various in-laws and their families and countless children. The principal of the local pre-school, Maryatou spent a year in England on a teacher-training course at Swindon College under the auspices of the Marlborough group. She remembers the UK with affection and says teachers in the two countries have more in common than not. “The principles are the same,” she says. “The only difference is in the resources available.”

As if to prove her point, each night her children cluster round me with their one book, a Gambian equivalent of Janet and John. They are word perfect and chant the stories at me in delight. It takes me a while to realise that they cannot read a word, but have learned it by rote.

During the day, much of the teachers’ time is taken up with meeting and greeting. The Gambians set great store by social niceties, which can take up a large part of the day. We had been coached in the appropriate Mandinka vocabulary, which goes something along the lines of:

“How are the people at home?” “They are there.”

“And how is your health?” “It is good.”

“Are you feeling well?” “I am well.”

And so on. Crack these rejoinders and you are rewarded by an explosive “Dohh” of approval - the vocal equivalent of a pat on the back. It is hard to know who gets the most pleasure out of these exchanges - the Gambians from hearing their language spoken by strangers, or us at their unalloyed delight and approval. Back in Britain it will seem strange when no one will look you in the eye, smile and ask: “And how are the people at home?” Each day, there is usually one group activity with plenty of free time for socialising within the host family. Our first visits involve several essential courtesy calls to the village elders. One of the first is to the nansimba, a dignified woman who is the head of the women’s groups in the village. She holds court and answers the teachers’ questions with regal magnanimity. She is a fierce believer in traditions, but astute enough to know that change is inevitable. A new road planned for the village will soon alter the entire fabric of society here, as tourist buses arrive and locals leave to look for work. Education, she declares firmly, is the way forward. “There is no limit to what it can achieve.”

But there is a limit to how you can achieve it. The Wiltshire teachers are all invited into schools to take classes and observe their counterparts at work. But while Mike Raine, head of humanities at John of Gaunt comprehensive in Trowbridge, comes bolstered with props including an inflatable globe, a headtorch and sheaf of photocopied maps for his lesson on climatic change, the teachers in the Gunjur secondary school rely on a pack of coloured chalk and a blackboard.

This gulf in resources affects every aspect of life. You cannot come to a place like Gunjur and not consider the acute dilemmas of development. The village has no running water, and each year young girls die when they fall into wells on the daily water run.

People succumb to preventable diseases - malaria is endemic - and female circumcision is widely practised. MBG has supported the establishment of a voluntary organisation, the Trust Agency for Rural Development, to address many of these issues. Director Michael Aylward and his Gambian team are working on projects that will improve health and prosperity and promote self-reliance for the village. The challenge, he says, is to develop leadership and management skills among local people and to make development sustainable.

Even so, it is still the Wiltshire teachers who come away learning most. Mike Raine baffles a group of Gambian teachers when he tells them that one of the biggest charities in the UK is the Royal Society for the Protection of Birds. They consider this to be inexplicably sentimental and are later appalled when they’re told of residential care for the elderly. In Gunjur, the old are revered and cherished and looked after at home. And Kathryn is taken to task by a village elder who can’t understand why she shares a two-storey house with just her husband. “He wanted to know what I grew in the garden,” she says. “He was astonished when I told him ‘grass and a few flowers’.”

At the end of the week, the teachers all achieve what they have come for - Tregoze has its video diary and enough hand-carved bric-a-brac to set up a stall at a car boot sale, and the pupils of Gunjur lower basic school have added to the pages of Geoff Anderson’s expanding global diary. But most importantly, all of us have had the chance to reconsider the way we look at the world and to know that we are now members of two families rather than one.

The Marlborough Brandt Group can be contacted at the Wiltshire World Studies Centre, 1a London Road, Marlborough SN8 1PH. Tel: 01672 516070. Email mbguk@compuserve.com