Frances Jaine was going to Thailand for her gap year with a friend. She had worked for months to save funds, and took care to book the trip with a firm that specialised in organising volunteering abroad.

“We hadn’t travelled without our parents before, and southeast Asia was a long way away,” she said.

The idea was that Jaine, then 19, and her friend would help out in a school in a remote Thai village for a month. They wanted to do something positive on their travels, rather than just loll around on a beach.

When they arrived they were in for a shock. They learnt that they were supposed to teach Thai culture, for which they were not obviously well equipped. “We ended up just doing drawing most of the time,” recalled Jaine last week, now 21 and a student at Leeds University.

Worse, the school closed every day at lunchtime and Jaine and her friend were left with nothing to do. There was no sign of the local travel rep, who, it was promised, would guide them in local customs.

So just two weeks into their contracts they left the village. It was a bitter disappointment. Not so much for the money they had wasted — they had paid the firm £750 each to sort out the placement — but for the sense that they had been no help at all in the village.

Each year some 200,000 young people undertake gap-year projects, spending on average about £4,000 each. Many are drawn to “voluntourism” — a specimen of well-meaning travel that also attracted princes William and Harry.

The government recently announced plans to send hundreds of new graduates on similar trips — with the additional effect of keeping them off benefits in recession-hit times. These taxpayer-funded gappers will help to build schools and improve sanitation in remote communities.

That’s the idea, at least. A Sunday Times investigation has shown that the goodwill of young volunteers is exploited by some companies sending them overseas — and that the work young people carry out while there is increasingly regarded as positively unhelpful.

IF YOU Google “volunteer gap year” the company that comes top of the search is Real Gap, which has seen rapid growth recently and was sold last year to Tui Travel as part of a deal worth £43.8m. Real Gap offers would-be voluntourists projects teaching in schools, raising awareness of Aids, working with orphans, and turtles, and injured wildlife, learning medical skills at a bushman clinic and helping elephants and landowners to live in harmony.

The projects offered by other companies are similar. They appear attractive, but people who sign up are not infrequently disappointed.

Sarah Byrnes went with Real Gap to an orphanage in Thailand in 2006. The firm’s reps, she says, had promised locals that the volunteers would help to rebuild the orphanage and put in water systems. But the volunteers were surprised when the local co-ordinator asked them to contribute £200 towards this.

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