The school is named Lagan College, after the river that divides Belfast. It looks down, from a hill on the southern outskirts of the city, on the Falls Road , Shankhill, and the other bleak ghettos which for so many years have been the flashpoints of bitter sectarian violence.
But Lagan itself is a world away from the Ulster of the headlines. For its pupils, all born within the past 13 years of bloodshed, are taking part in a remarkable attempt to unite Ulster's warring communities. In this province, where religious segregation is the rule, Lagan is the first fully integrated secondary school to be established in over a century.
There is an equal number of Catholic and Protestant pupils, teachers and governors, and the curriculum emphasizes the common Christianity and culture of the two communities, rather than what divides them. The fact that Lagan has survived into its second year amounts to a small miracle, in a society that had ceased to expect them.
Lagan grew out of the dissatisfaction of a handful of parents with a state education system which, they felt, only reinforced existing fears and hatreds. Protestant children in Ulster go to Protestant schools, Roman Catholics to Catholic schools - partly because the schools are located within their own sectarian communities, but also because each school only provides religious instruction for children of its own denomination. Only about one child in every 100 crosses this religious divide.
One of Lagan's founders, Tony Spencer, a Catholic university lecturer, so despaired of these religious barriers that he sent four of his five children to Protestant secondary schools. But the children paid the price of his idealism; they frequently came home complaining of harassment.
One of his daughters, during a French lesson, found herself having to recite ''Nous sommes tous Protestants'' (we are all Protestants) along with the rest of the class. When the time came to send his fifth child, Jane, to a secondary school, he decided there was no point in waiting for Ulster's education authorities to come around to his way of thinking. He would have to start a school open to all, regardless of their religious beliefs.
There were, he discovered, plenty of other parents who had the same ideas. Anne Kinsella, whose son Michael was one of the first to enroll at Lagan, sums it up like this: ''If Lagan College had not turned up, I would have considered leaving the country, rather than send Michael to a segregated school. I wanted him to do well academically, but more important was the way he learned to treat other human beings.''
Another parent who was willing to risk being ostracized by friends and neighbors was Eleanor Bailey, whose two daughters are at Lagan. She says: ''My children spent the first eight years of their lives living in the (Catholic) Falls Road. We have seen it all - the shooting, the hatred, the unbelievable divisions between the religions. I was determined that my children should experience something different.''
Lagan's first 28 pupils began lessons in the only premises available - two makeshift classrooms in a ramshackle scout hut in South Belfast. Even the desks and blackboards had to be cleared away each night, because the hut was needed for other purposes.
Some of the children came from towns as far away as Lurgan and Antrim, 22 miles from Belfast, many of them being ferried in aboard a bus borrowed from the Northern Ireland Peace Movement. They wore gray school uniforms in the best British tradition - but left their ties and school badges at home, for security reasons. Lagan parents, fearful of laying their children open to attack by sectarian extremists, did not want them to be too easily identifiable.
There were the inevitable shows of hostility at first: a handful of the Rev. Ian Paisley's supporters threatened to picket the school; two Lagan pupils were stoned by youths at a nearby railway station; and the occasional school window has been broken. But by Northern Ireland standards, opposition has been remarkably low-key. Instead, unexpectedly, there have been many spontaneous expressions of support from members of both communities. Today, 14 months after Lagan opened, all pupils wear their ties and badges, with the motto ''Ut Sint Unum'' - that they may be one.
But Lagan teachers stress that they are not trying to play down differences. The school is as markedly Christian in ethos as any other in Northern Ireland and the children are encouraged to take pride in their own backgrounds. What makes Lagan revolutionary is its approach to religion, and to other traditionally divisive subjects such as history and literature. At Lagan there are three religious education classes a week - two for all the pupils and one reserved for denominational teaching. The shared lessons are taught alternately by a Protestant and a Catholic, who take pains to explain doctrinal differences. History is taught from a variety of textbooks, so that controversial events are seen from both sides of the fence.
Literature lessons concentrate on the best of both British and Irish writing. The Irish language and Irish dancing are proving popular after-school options - mostly among the Protestants. Thorny issues that previous generations have ignored to their cost, form the subject of lively classroom debate. One small boy, raised in a Catholic working-class ghetto where prejudices are deeply ingrained, spent his first day at Lagan asking each classmate his religion. A few weeks later, when a visitor asked him his, he replied with some impatience, ''Sure, and what does it matter?''
Says Mr. Spencer: ''They have come to react like normal children anywhere. The Protestant kids are no longer startled when the Catholics cross themselves at morning assembly. And my daughter Jane resents being asked how she likes the Protestants at Lagan because, quite simply, she no longer differentiates.''
Most of the kids admit to having been nervous and uneasy about Lagan at first. As 12-year-old Patrick Gilmour says: ''I was afraid that my friends in the neighborhood might stop talking to me, but they treat me as though I went to an ordinary school. Now I wouldn't go anywhere but Lagan, because there are more interesting people there.'' Firm friendships have been formed in the playground, and Protestant and Catholic children visit each others' homes, even in working-class districts.
It is too soon to predict how Lagan will do academically; but all the signs are that the children - like all those involved in the venture - feel a responsibility to make Lagan work. It already has one major success under its belt: a few months ago, the school entered a competition organized by the Churches Community Council, in which all Ulster secondary schools took part. Although they were up against some tough opposition, including 16-year-olds from some of Ulster's best-known grammar schools, Lagan's 11- and 12-year-olds, who submitted a project on the Great Famine, coolly walked off with first prize.
Lagan, at the start of its second year, now has 90 pupils - and none of the original 28 have dropped out. As the school's reputation has grown, so has the breadth of its appeal: more and more children from the ghetto heartlands are enrolling - a snub for Lagan's early critics who predicted that, like so many liberal initiatives, it was destined to remain hopelessly middle class. The Roman Catholic and Protestant clergy, both distinctly cool toward Lagan at the outset, are gradually coming to accept it. Even the Irish Primate, Cardinal O'Fiach, breaking with centuries of tradition, has cautiously welcomed the experiment. And next year, according to headmistress Sheila Greenfield, Lagan may have to start turning applicants away . . . if it survives that long.
For although parents and teachers alike dismiss the possibility of failure, the fact is that Lagan is facing critical financial problems. Unlike ''normal'' schools in Ulster - the segregated ones which operate within the system - Lagan does not receive a penny from the state. It will have to go it alone until 1984, to satisfy the authorities that there is sufficient demand for integrated schooling to justify a subsidy.
The authorities have paid little attention to the results of opinion polls, which show that more than 70 percent of the people of Ulster want mixed schooling. ''My main worry,'' says Mr. Spencer, ''is that the problems we have in being accepted into the system may deter others who want to follow our example.''
In the meantime Lagan has to live a hand-to-mouth existence, depending for funds entirely on charities and on parents - many of whom have had to make considerable financial sacrifices. The fees are $:600 ($960) for those who can afford them; poorer parents, incuding several who are unemployed, are means-tested and pay little or nothing. The balance is met from scholarships. One of the better-off parents, who pays the full fees, has had to cancel the family holiday this year; Mrs. Bailey, a cleaner, and her farmworker husband, have sold the family car so that they can contribute $:47 ($75) for each of their two daughters' education at Lagan.
A public appeal to raise the estimated $:400,000 ($640,000) Lagan will need to ''buy'' its way into the system, has so far raised a quarter of that. Most of the money has come from British charities, from America's Northern Ireland fund, as well as individual Americans and Canadians. In keeping with Lagan's unorthodox approach, an Anglican nun from Belfast hitchhikes around Europe on regular fund-raising missions.
New premises for Lagan are also urgently needed. Although it is no longer housed in the scout hut, but in a whitewashed bungalow in the leafy Castlereagh hills, space is short and the facilities inadequate. Two of the classrooms are in prefabricted buildings in the schoolyard. There is no art room, no gym, no library or science laboratories. The present site has other drawbacks: because it is in a predominantly Protestant area, it is feared that Catholic parents will be reluctant to send their children there.
The parents chip in with fundraising and do what they can to help out the staff of four full and six part-time teachers. They help with the supervision, the cleaning, and run the snack bar. Lagan's accountant is a parent. One mother does half the filing, another does the rest. But the reason for parents' involvement with Lagan is not simply financial. As Mr. Spencer says: ''You don't just say to your children 'off you go and get integrated.' You've got to get everyone involved.''
Yvonne Gilmour is a fairly typical Lagan parent. She is the school's transport officer, sits on the Parents Council, runs a sewing class, and organizes social activities such as the regular discos, where Protestant and Catholic parents, as well as children, are encouraged to mix. It seems to be working: ''The Lagan experience is changing people - not just the children, but people like myself,'' says Yvonne. ''I never mixed with Catholic women until Lagan opened, now I know several from Catholic districts and the unthinkable is happening. We're visiting each other's homes for coffee and a chat. Religious and social barriers are beginning to crumble.'