text: Many people say that is just supply and demand.
  But since a Devon father's Facebook "rant" on the subject went viral, more than 165,000 people have signed a petition calling on the government to "cap" price rises in the school holidays.
  The issue will be debated by MPs later, but what solutions might help holidaymakers?
  The popular petition, now the fifth most signed since the government set up its e-petitions website, asks UK authorities to "enforce action that caps the percentage increase on holiday prices in school holidays".
  Mother-of-two Donna Thresher, from Essex, set up the petition and said holiday companies should also be forced to advertise term-time holiday costs when selling trips in the school holidays - allowing customers to see the difference.
  Theresa Greenwood, who has four children and lives in Manchester, said a cap could stop many parents being "priced out of even the cheaper end of the market".
  Another parent, Debbie Bower, from Sheffield, said: "It is wrong to allow 300%-plus increases in school holidays for so-called supply and demand."
  And father-of-four Nigel Walton said a cap of 50% above term-time prices was needed to stop holiday companies "profiteering".
  But responding to the e-petition, the Department for Business, Innovation and Skills said it was "for businesses to decide the market worth of their products".
  And travel journalist Simon Calder said: "If that [regulation] were to happen then you might as well just close down the whole holiday industry because they simply could not make any money."
  Richard Singer, of travel deals company Travelzoo, set up an e-petition calling for Airport Passenger Duty (APD) to be suspended or reduced during the school summer holidays.
  The petition, which has been signed by more than 38,000 people, says the move would help end the "parent trap" of inflated holiday prices.
  Information gathered by Travelzoo last year suggested holidays from the UK to long-haul destinations were 40% more expensive in the "peak" summer weeks, and a survey found 80% of families felt "penalised" by the prices.
  Mr Singer said a "creative solution" was needed, and suspending APD should be part of that.
  APD ranges from £13 to £188 per passenger on most flights, with lower rates for economy passengers and shorter flights.
  Zoe Keene, a member of Holiday Price Increase, a Facebook group set up to campaign for reduced prices, said tax breaks would be "easier to implement" than trying to get holiday companies to cut prices.
  Responding to the Travelzoo e-petition, the Treasury said APD played an "important part in supporting this government's stabilisation of the UK's public finances".
  APD is paid by airlines - not directly by passengers - and the Treasury said there could be no guarantee of savings being "passed on fully" to customers even if the tax was cut.
  The Association of British Travel Agents said the travel industry "would welcome" staggering of school holiday dates to avoid high demand in short periods.
  It said a poll of its members last week found 85% favoured "staggering by region" in the UK, a system already used in several European countries.
  Mother-of-one Emma Lowther, from Plymouth said: "I think they should stagger some of the term times so that demand for holidays would go down and instead would be spread out, so holiday companies would not have 'peak times'."
  John Lamerton, also from Plymouth, whose wife is a teacher, said: "Staggering term times seems to be the most common sense solution I have seen suggested."
  He said staggering would "soften the blow" of synchronised holiday dates and create a more stable market for travel firms with "increased 'holiday' periods for family-friendly destinations".
  But mother-of-four Adele Large, from Evesham in Worcestershire, said staggering holidays would not be "fair on those with children at different schools".
  "Childcare would be a nightmare," she said.
  Since September 2013, head teachers in England have been able to grant absences for holidays only in "exceptional circumstances".
  A petition on campaigns website 38 Degrees, calling for the rule change to be reversed, has been signed more than 200,000 times.
  Mother-of-four Emma Matthews, from Brixham in Devon, said: "I think they should go back to how it was last year. Why break something that works?"
  She said rules against term-time breaks should "target the parents of children whose attendance is poor".
  "At the moment they are corralling ordinary, hard-working parents down a path they do not want to go down and forcing us to either break the law or give up family time," said mother-of-three Caitlin Hartley-Curran, from Huddersfield.
  Liberal Democrat MP John Hemming, who put the holiday prices petition forward for debate in Parliament, said "greater discretion for head teachers in some circumstances" was one possible solution to the problem.
  A Halifax survey published last week suggested 41% of parents would take their children on holiday during term time despite the fines - which are £60 per parent per child. These double if they are not paid within 28 days.
  Paul Cookson, whose Facebook post sparked mass support for the petition, said its call for price regulation was unlikely to be successful.
  He said it raised awareness, but the best chance of success would be for a major holiday provider to voluntarily stop increasing prices during school holidays.
  "The ideal is to work with the holiday companies directly to advise them on the business of reduced-priced holidays in these set times - it can be done," he said.
  Mr Cookson said such a move would bring a company thousands of loyal customers, and could force others to follow suit.
  He said there was no "one answer" to the problem, but some smaller companies already kept their prices stable during school holidays and more could be convinced to do so.
  Many people believe the only viable solution is for people to refuse to pay peak-time holiday prices.
  Victoria Bacon, of ABTA, said families should book early and "be flexible" by avoiding peak days and destinations.
  Travel journalist Simon Calder agreed, saying people should find a "way around it" by avoiding popular routes, or trying holidays like camping, where prices do not rise so sharply.
  Father-of-two Peter Syme, from Perth, said: "Take your time and search out small owner-operated businesses and do not just default to booking with huge PLC businesses."
  One such business is run by Sarah Guy, who offers camper van holidays on the Isle of Wight.
  "I do not increase during school holidays, with the intention of supporting our local tourism sector and fellow parents," she said.
  But with "all hands on deck" in the school holidays, her family has also found itself in trouble over taking a break - she said she was recently fined £360 for taking her children away during term time.
target: Is it fair for airlines and holiday companies to charge much more during the school holidays than in term time?