Francoise Leake received an unusual phone call on her first day as head of Westborough high school in Dewsbury, West Yorkshire. The voice on the other end of the line belonged to Denis Ripley, deputy chair of education at Kirklees metropolitan district council, and he was calling to commiserate with Ms Leake on her appointment. He knew Westborough, an 11-16 secondary, was about as low as a school could get.

If she still doubted the size of the challenge that lay ahead, her first lunchtime patrol left her in no doubt: as she strolled out to the playground, she was greeted by a group of mounted policemen. These, she was told, were necessary to keep her pupils, 70 per cent of them Asian, apart from those at the neighbouring Roman Catholic secondary, St John Fisher.

This summer racial violence has ripped through Britain’s northern towns and cities, and an inquiry into the Bradford riots chaired by Sir Herman Ouseley, former head of the Commission for Racial Equality, has identified racially “segregated” schools as a major factor in the unrest.

However, the scene in Dewsbury is not from this summer, but from 15 years ago when the town became a racial flashpoint in the way that Oldham, Burnley and Bradford have since become. Francoise Leake, now in her late forties, has remained loyal to her school and is still head of Westborough. The transformation she has helped to bring about should give hope to the Government as it attempts to bring down racial barriers in other northern schools.

Back in 1986 Denis Ripley, who went on to become chair of Kirklees schools and today is chair of governors at Westborough high, received death threats when a group of white parents who had withdrawn their children from a local primary school - because it had a majority of Asian pupils - were refused permission by Kirklees council to send their children to schools outside the catchment area.

A local publican inflamed the row by offering his pub as a schoolroom, and Dewsbury hit the headlines for almost a year. The case went to the High Court; Kirklees lost on a technicality and the wounds ran deep. But an enormous amount of work has been done to heal those wounds, not least on the part of Westborough.

Dewsbury has much in common with Oldham, in that it is a former mill town with a large working class, and segregated Pakistani and Indian populations. The teaching mosque in Savile Town, a largely Muslim area, is the biggest in Europe. As in Oldham, the British National Party fielded a candidate in June’s general election, but while the BNP gained 17 per cent of the vote in Oldham, in Dewsbury it polled just 4.5 per cent, down nearly 1 per cent on the 1997 election. No one pretends that racial tension has disappeared, but since the 1980s great strides have been made towards fostering a culture of tolerance.

Francoise Leake did not shy from her task. That first image of police in her school fuelled her desire for change, for Westborough to become a high-achieving, truly multicultural institution. “I came with the philosophy that schools in this sort of area can make a difference,” she says. “We are here to serve this community. These kids are not going to go away, they don’t have that opportunity, but we do have the opportunity to make this one of the best schools in the country.”

Her determination to tackle racism, and what she saw as the underlying problem of low self-esteem, has brought about astonishing improvements that have rippled out to the communities of central Dewsbury. Mr Ripley might have apologised to Ms Leake, but he has never regretted her appointment. “She goes out there and talks to people, and they trust her because she doesn’t run away from the issues. They are faced up to.”

The mounted police have gone, the school lives comfortably with its Catholic neighbour, pupil attainment has risen (from 8 per cent of pupils gaining five GCSE A-Cs when league tables began in 1992, to 39 per cent last year). Westborough’s approach to race relations and equal opportunities has earned it beacon status, and in January Ofsted commended the school for promoting “excellent” relationships among pupils. Most students - 48 per cent of whom have English as a second language - go on to further education, and Ms Leake now has the satisfaction of seeing former pupils return to Dewsbury as graduates, setting up businesses and going into the professions.

Ms Leake has given pupils such as 16-year-old Nadia Ali the confidence to step in and confront racial aggression both within and beyond the school boundaries. Nadia didn’t think twice about intervening when she saw a group of Asian lads picking on a white youth in Ravensthorpe, the largely Pakistani area where she lives.

“I just went in there and told them to back off,” she says. “I told the English lad to walk away from it, that I would deal with it. The Asians gave me a lot of slack (bother). They said ‘whose side are you on?’, but I gave them a piece of my mind, that it wasn’t fair to pick on one person. They couldn’t believe I was doing this. The expression on their faces said it all. But at Westborough we grow up knowing that bullying and racism will not be allowed. We are taught constantly about the effects it has on people and we grow up not tolerating it ourselves.”

Westborough has 835 pupils, split 5050 between Asians and whites, and a governing body reflecting that mix. Pupils will tell visitors that discrimination between pupils or between staff and pupils is not tolerated. The atmosphere is calm and friendly. “This is a good school,” says Isma Kayani, 15, “because people from different backgrounds mix with each other. Everybody is equal.” Lianne Kaye, 13, says the school works hard to help pupils understand each other’s cultures. “We learn all about their religions, how they say their Koran, that kind of thing.”

Zulqarnain Shah, 16, came to Westborough from another high school where he had been bullied. “They would put bins over my head when I went into a classroom,” he says. “But here it’s different. You are treated as an individual, with respect.”

When the initials NF were scrawled on an outside wall, pupils were appalled and the graffiti was speedily removed. Linda Tempest, an assistant head, says: “We try to see everything as an opportunity, not as something negative. This gave pupils an opportunity to express their disgust at racism.” During election campaigning, the BNP leafleted outside some schools, but did not bother with Westborough. Perhaps it knew there would be no point.

The transformation of Westborough has required “constant negotiation”, says Mrs Tempest, constant reaching out into the community, working with parents, mosque and community leaders, and facing up to tensions.

School staff run a homework helpline and study-support centres. One of these, in the Sulfia Centre in Ravensthorpe, is next to the mosque so that pupils can be helped with homework before they begin their Islamic lessons. Mohammed Razaq, a Labour councillor who has children at the school, says that white children also attend the centre, to use the IT facilities. “I think that is unique, Asians and whites sitting side by side at the mosque,” he says. “That has got to promote understanding. That is bound to ameliorate some of the tension. I have been amazed to see that.”

Mohammed Ishaq, chairman of the mosque and Sulfia centre, says the white visitors have a positive attitude: “They come here peacefully and respect it. It helps to improve race relations. I would like to see all mosques do this sort of thing.”

Senior teachers have spent hours meeting parents in their homes, persuading them of the benefit of attending parents’ evenings, and explaining the nature of the curriculum.

Mohammed Habib, who teaches Urdu at Westborough, is also the school’s community liaison teacher; Shazia Rasheed, a business studies teacher, helps to co-ordinate study support and works with parents. Their presence, Ms Rasheed believes, helps to give the Asian community confidence in what the school is trying to achieve. “We have their trust. They know their children will be safe here and that their culture will be respected,” she says. Attendance at parents’ evenings, once as low as 12 per cent, has now grown to more than 90 per cent. The demand for Muslim schools or segregated education has diminished as Westborough’s reputation has grown.

In school, boys sit with girls, white with Asian; pupils’ prejudices are continually challenged. Staff keep vigil throughout the day, working with children at lunchtime, organising games and competitions, standing at the school gates, and seeing children safely off the premises at the end of the day. Difference is respected. Muslim girls wear headscarves, and a quiet room with a stained-glass window has been set aside off the main reception area where pupils and staff can pray or be alone. When children arrive in Year 7 they are given a week-long induction called “Westborough ways” in which the effects of bullying and racism and the importance of respect for each other’s cultures are spelled out.

This message is reinforced in tutor groups and in personal and social education throughout each pupil’s school career. In addition, children are encouraged to praise each other and to talk through problems. Ms Leake has never permanently excluded a pupil. “I am not saying we have all the answers,” she says. “We work with all the agencies, and not every child does five years here. Some take time out. We are flexible about how we handle some issues, and we always work with the parents.”

The driving force, she says, has been a commitment to equal opportunities in all aspects of the school’s work. “We are committed to it at all levels. My staff don’t ever give up. They will always go the extra mile, find another way around the problem.”

Linda Tempest, who has been at Westborough for 22 years, can see a real difference in the community. “Children’s perceptions at this school are now so different from a previous generation’s. That empowers them when they go out in the world. It’s a real role that education has to play.”

Francoise Leake has been unsuccessfully headhunted for Fresh Start schools on several occasions, but is committed to the long haul at Westborough. “We have begun to see real changes in the last five years. It takes that much time,” she says. “In this school pupils learn how to trust each other, and we hope they take that out with them into the community. I cannot believe that they would ever turn against each other.”