In the week that A-level results are out, Voluntary Service Overseas, the international development charity, said badly planned so-called "voluntourism" schemes by companies making a business out of channelling public sympathy were having a negative impact on young people and the communities they worked with.
Events such as Live 8 and the Make Poverty History campaign have fuelled the desire of many young people to volunteer. However VSO - whose average volunteer age is 44 - is concerned that increasing numbers of students are paying to be involved in purposeless projects that do not offer constructive help to deprived communities.
One volunteer, named only as Eva, now 26, paid £2,000 to spend six months volunteering with environmental projects in Mexico.
But when she arrived, she found there was little for her to do and instead of getting involved in rural projects where she felt she could make a difference, she spent the majority of her time inputting data to spreadsheets.
"It was depressing to be doing administrative work all day as I had spent six months at home working in an office to save up enough money to fly to Mexico," she said.
"I was told I would live with a local family when the reality was that the family simply rented out a room, and the integration that I had been promised was non-existent."
VSO has two programmes for 18-25 year olds, for which it provides flights, accommodation, training, visas and a living allowance.