But on Wednesday, just three working days after the torching of Waltheof School in Sheffield, the Year 11 pupils were already back at work in emergency accommodation in nearby Stradbroke college. All were revising for the GCSEs they will have to take in five weeks’ time - though minus their coursework, which was incinerated in the blaze.

The younger pupils will attend coffee-and-biscuit meetings with their teachers this Thursday and Friday, “mainly to reassure them that their teachers still exist and that they will not be separated from their friends,” according to one senior teacher.The local education authority’s team of educational psychologists is on standby to help the pupils come to terms with the trauma.

On Tuesday afternoon, a meeting between Waltheof’s head, Andy Gardiner, and Sheffield council’s education chiefs decided that the rest of the pupils will return to work at the Waltheof site on April 24 after the Easter holidays, using the few outbuildings that escaped the inferno (a sports hall, an English block and a few decrepit prefabricated huts).

From September, the staff will be equipped with “good quality temporary accommodation” until the new school, which the Labour council has pledged to build at an estimated cost of Pounds 7 million, is complete.

“In other words we are going home,” Andy Gardiner told his shell-shocked staff, crammed like refugees into their crisis headquarters at a local in-service training centre. This was greeted with a loud cheer - the teachers had feared that they would be scattered across the city in the months to come.

The fire, which started at 10.30pm on Thursday last week and ate rapidly into the fragile 1960s architecture, caused damage worth about Pounds 3 million in financial terms, but the waste of human effort is incalculable.

Assistant head Maggie Payne said: “We’ve lost everything really, all our equipment, teaching materials, pupils’ records of achievement, coursework, art, computers ... all we emerged with was one set of duplicate registers held by a welfare officer. I met one pupil who was crying as she stared at the ruins. ‘Everything I’ve got is in there,’ she said.”

Ever since he stood until dawn last Friday watching his school burn to the ground, Andy Gardiner has been reiterating one message - that a school is more than bricks and mortar. In a letter drafted and sent to all parents while the wreckage was still smouldering, he told them: “Waltheof school still exists. Our school has never been just buildings - its heart is the people, all of them, who come to work or learn in it.”

This is the biggest and most expensive fire Sheffield has ever had, and will inevitably raise questions about security. Police were still appealing for information this week about the group of youths seen near the school on the night of the fire, as forensic science teams picked over the rubble (arson is strongly suspected but not confirmed).

Sheffield education spokesman Martin Gazzard said: “We are constantly reviewing security arrangements, but if somebody is really determined to get in they will.” How much of the bill for rebuilding will be met by the insurers is not yet clear, Mr Gizzard said.

o Just five days after the blaze at Waltheof school in Sheffield, another headteacher, Roger Cunningham of Kitwell infant and junior school in Bartley Green, Birmingham, has been left without a school to to teach in.

The fire, which started on Tuesday night, has caused Pounds 400,000 worth of damage, gutting the main hall which also served as the dining and sports area, according to a Birmingham education spokeswoman.

Health and safety inspectors are currently assessing whether any of the classrooms are fit for use. A police spokesman said that the fire was being treated as suspicious.

Malicious fires caused damage to schools worth Pounds 22 million in the year 1992-93, according to the Department for Education; the only consolation being that this compares to Pounds 42 million in 1991-92.