The legal battle over term-time holidays reaches the Supreme Court today.
A father last year won a landmark High Court ruling blocking a £120 fine for taking his daughter to Florida during term time without a school's permission.
Two senior judges declared that Jon Platt was not acting unlawfully because his daughter had a good attendance record during the rest of the year.
Isle of Wight Council, the local education authority that took Mr Platt to court, is asking five Supreme Court justices to overturn the High Court judgment in his favour.
It does so with the Government's firm backing.
The High Court judges upheld a magistrates court ruling that Mr Platt, originally from Northern Ireland, had no case to answer.
Mr Platt, who has been contacted by hundreds of other parents over his case, argued his daughter's total attendance was over the 90% threshold contained in the Isle of Wight policy on regular attendance.
He requested permission to take his daughter out of school, but his request was refused by the head teacher.
He was issued with a fixed penalty notice of £60. He failed to pay and was sent a further invoice for £120, which he also refused to pay.
When he was prosecuted, magistrates refused to convict him.
At London's High Court, Lord Justice Lloyd Jones and Mrs Justice Thirlwall dismissed the council's renewed challenge and said the magistrates were entitled to take into account the "wider picture" of the child's attendance record outside of the dates she was absent on a seven-day trip to Disney World in Florida in April 2015.
Why are term-time holidays banned?
The Government maintains that missing even a few days of school is detrimental to a child's education.
The Department for Education published research last year which indicated that every day missed reduced the chances of a pupil achieving 5 GCSEs at grade A-C.
Families complain that holidays in official holiday periods are up to four times more expensive, and local councils have reported the number of breaks in term time is increasing.
What are the rules?
Since September 2013, under guidance from the Department of Education, children can only be taken out of school during term time in “exceptional circumstances”.
If they skip school during term time, parents face a £60 fine.
That doubles to £120 if it is not paid within three weeks.
Those failing to pay face prosecution – and a fine of a maximum of £2,500 following prosecution, or up to three months in prison.
How has the case impacted the policy?
The decision caused a surge in term-time bookings all over England.
Controversy was first triggered when the Government ordered a crackdown on school absences in 2013.
An BBC investigation has found that 35 English councils have changed their policy on fining in the wake of his High Court victory.
A further five are reviewing their policy, while 28 have withdrawn fines imposed on parents.
The survey highlights the contrasting approach to fines around the country, giving rise to allegations of a post-code lottery.