Headteachers have long said that pupils must not miss class except for exceptional reasons and that parents will face £50 fines if their children are off.

But now – with the Olympic torch coming to Sussex in July – youngsters and their parents are being told for one day all this could change.

Councils have issued guidance to staff about what to do if parents ask for their child to have a day off to watch torchbearers in the county.

West Sussex County Council has suggested that schools may wish to consider organising an educational visit to see the event.

But a spokesman said: “It really is for individual schools to decide at the end of the day.”

He added: “Respond positively to requests from parents for an authorised absence of their child from school for part, or all, of the relevant day.

“This will, of course, depend greatly upon the location and timings of the torch relay most appropriate to your school.

“The Department for Education has reminded us that the decision to grant leave of absence is entirely at the headteacher’s discretion in consultation with the chair of governors and other schools in the locality.”

East Sussex County Council said that because the event was “a once in a lifetime opportunity” children would probably be allowed off school.

A spokeswoman said: “In normal circumstances, of course, headteachers would not authorise absence unless the circumstances are truly exceptional.

“However, we do recognise that the Olympic torch procession through East Sussex is a once in a lifetime opportunity that will have historical significance for our county and our country.

“We are encouraging schools to incorporate events within the school day if possible, but because of the exceptional nature of the event, we are also taking a more relaxed view on decisions being made by headteachers to authorise absence and make changes to the school opening on that day.

“We do hope as many of our pupils as possible will get the chance to be involved in marking the event in some way. Headteachers will be ensuring, however, that students sitting any exams are not disrupted, and that any changes to the school day are communicated to parents as early as possible.”

A Brighton and Hove City Council spokesman said: “This is for individual headteachers or governing bodies to decide.”

St Wilfrid’s in Eastern Road, Haywards Heath, said they were aware that some parents were planning to take children to see the torch and to do this must write a letter to the school so the absence would be authorised.