The spending was lavish — £5 for a jar of chutney, £50 for a few baubles on a length of chain. The cakes on the refreshment stalls, seemingly lifted from the photoshopped pages of a colour supplement, cost — were you able to force your way to the front of the queue — more than those at the boutiquey bakeries round the corner. Parents at this school fair, held last Saturday in a South London suburb, barely raised an eyebrow at being asked to drop £4 for a burger or £5 for raffle tickets.

The school is so popular that most feel lucky to have secured their children places and reason that spending generously at fundraising events is cheaper than paying school fees. And, in return for their largesse, the parent-teacher association (PTA) had put together quite a production: three playgrounds of stalls, games, shows and attractions that would have raised about £12,000.

And this epic scale is by no means isolated, as schools become more and more reliant on the money raised by the PTA, and the PTAs become more and more ruthless in raising the money. But while everyone can agree that helping to fund a library, some playground equipment and drama productions is all to the good, the sheer level of competition between parents to be seen to give the most has become slightly unsavoury.

Some complain that they are “not good enough” to volunteer their time; others have their efforts sneered at. “I baked a tray of muffins for my daughter’s school and they weren’t even displayed, presumably because they weren’t as perfect as the ones made by all the domestic goddesses in reception,” says one stalwart of the cake stall. “They sold them off cheap in mixed bags at the end.”

Others find the size of the donations daunting. “There’s no point giving a box of scented candles for the raffle when you know that one of the parents works for BA and can get flights to Barbados,” says a mother whose children attend a state primary school in the “pilot belt” of Surrey. Others cite vintage wines and offers of a week’s stay at a Mediterranean villa as common prizes for the now-obligatory auction of promises. “Although they are lovely prizes, it does cause resentment because some parents come to be seen as more valuable than others,” says one teacher in a well-regarded North London primary.

And, as with all displays of charity, the generosity can lead to one-upmanship. Last year at a school near Milton Keynes a group of dads banded together to form the Barbie-Kings, offering to cater a barbecue for up to 20 people. Bidding started at a brisk £300 and eventually stopped just shy of £1,200. “It was obscene,” says one of the mothers who organised the auction. “Lots of the fathers work in finance and it was just a form of willy-waving.”

It is a truism that PTA committees have become slicker, more polished forces as competition between schools has grown ever stiffer. But it is not simply the league tables that have become cut-throat; many schools keep a very wary eye on their rivals’ fêtes in order to up the ante at their own: they had go-karts so we must have dodgems; they had a burger stand so we must have a hog roast. Ultimately, most state schools, even in privileged areas, have some degree of social mix in their intake, and the excess of such fairs risks alienating parents — and children — from poorer, less well-connected families. “At our summer fair a local deli donated a lot of organic meat, which some parents barbecued,” says a mother from West London. “They wanted £4 for a sausage sandwich and £6 for a steak baguette; they couldn’t understand why some parents couldn’t pay that. They just thought they were being tight.”

Perhaps the tide is turning against the venality of these bigger events. One mother whose son attends a West London school says that this year the fair was very back to basics; offers of sponsorship were turned down and a deliberately home-made ethos was adopted. “It was wonderful — so much effort went into it, but it was for the parents and the children. It made us feel like a community again.”

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