Watterson’s shop - three of whose workers died on Saturday, August 15 - is doing steady business. Oxfam, where two young volunteers were killed, had a steady trickle of customers. Further down Market Street, close to the blast site, shoppers were bargain-hunting in a bomb-damage sale.

Local schools are seeking the same mix - recognising what has happened but trying to make a start on getting back to normal. When it comes to finding university places or jobs, there will be no allowances for pupils from Omagh and surrounding villages. Exam results are still vital.

William Harper, head of the 430-pupil Omagh high school, opened the school early to give pupils and parents a place to talk. Some teachers and ancillary staff went back early to help.

The school lost two pupils, three former pupils and three parents. Many others were injured.

One was left paralysed, another lost an eye; in a third case shrapnel went through a pupil’s leg and into the other.

Mr Harper said the full horror struck him as he deleted 15-year-old Lorraine Wilson’s name from the computer records.

Schools do not yet know exactly how many pupils were hurt or affected. The secondaries have been asking primary schools about the impact on pupils transferring to them. “There was a sense of gloom and grief. It is a hard task to try to lift pupils,” Mr Harper said. “There is still more disbelief than anger.”

Pupils and relatives have died before but no school in Northern Ireland has had to deal with grief and bereavement on such a scale. “It needs focus and leadership in a difficult situation. It is about responding to the pupils’ needs and there is also the question of keeping the school running,” he said.

The Western Education and Library Board, based in Omagh, has brought in trauma specialist Elizabeth Capewell, whose experience includes the massacre of children in Dunblane. She has been visiting schools and running short courses for teachers.

But Omagh high school has coped largely on its own, trying to keep a normal routine, using classroom teachers, a few of whom have counselling qualifications.

“I’m careful of some of the ideas going round,” Mr Harper said. “I don’t believe in disrupting classes or sitting in circles to contemplate death, but I’m conscious that some pupils may need specialist counselling. If so I can get it through the local health board, but no pupils have asked for it yet.

“We have to rely on our own strengths, among teachers and pupils. Some will need a lot more support than others. We need to look out for the person who is quiet or withdrawn; some may be introspective and think about it all the time.

“The pupils are still a bit subdued and are especially well-behaved this year. Perhaps when we begin disciplining pupils again we will know we have returned to normality. The best thing pupils can do is work normally and enjoy school and play. At the end of the day they must work hard and pass their exams, ” Mr Harper said.

Donal McDermott, head of St Patrick’s boys’ school, is helping 14-year-old Gareth McCrystal, whose mother was killed, to cope. As agreed with the family, Gareth simply arrived back in school with his friends and attended a special prayer service, but was not singled out for mention.

As well as boys who have obvious injuries, teachers will look out for others who have been affected by the death or injury of friends and relatives, or by witnessing the gruesome scenes. The signs could be if a child’s work deteriorates or he is sleepy.

“Boys are not supposed to cry because of the macho image, so some could have a delayed reaction. That makes it more difficult for us as a boys’ school, ” said Mr McDermott. “Sometimes the reaction could take many months. You can’t shorten that if the kid is not ready to let it out.” Teachers must turn to outside agencies if special help is needed.

“I explained to Year 12 today that it is their final year. This is not to negate what happened on August 15 but the purpose of the school is to get them through their exams,” he said.

Like Mr Harper, he believed pupils felt it was disrespectful to misbehave. He describes the mood as “muted” but the atmosphere is quite chilling when the bomb is mentioned. The school intends to give pupils an opportunity, whether through visual arts, writing or talking to express their emotions, and to progress from there.

“I have told the boys there is nothing wrong with laughing,” said Mr McDermott. “There can be a lot of emotions, from happiness to grief. The senior boys in particular know we have to move forward. We have to get on with what we are good at, the job of educating.

“We should also say we can build a better future. We need these kids to be able to trust again. That has been damaged because somebody could do this to their town.”