It was to be the trip of a lifetime. It was March and the seven 16-year-old girls, all Ranger Guides, had been saving and planning for months. At Dublin Airport, they were bursting with excitement. They stopped in Italy overnight and met up with a local Scouts group, then flew to India.

When they got off the plane, the heat was the first thing to hit them. Then the smells and the noise. But on the bus into town they got a landing of a different sort.

As they entered Bombay, their chatter gave way to silence, and soon they were all in tears. The reality of poverty was all around them. This holiday was about more than getting a tan. They had come to help.

Many Irish people are turning away from the two-week fun-in-the-sun package and seeking out something more meaningful to do with their free time. Teachers will go to Africa for a few weeks in the summer to help in shanty schools; nurses will head for Asia to work with people dying in slums.

When Conor Hughes, from Dundalk, appealed for local workmen to give up their holidays and go to Romania for a fortnight this month to build an orphanage, he was inundated with calls.

The Tanner Romania Mission had bought a cottage to accommodate care staff and needed a purpose-built wing for nine physically disabled children.

"If you wanted a man to come out and fix your water pipe it might take months, but here were people delighted for the opportunity to help," says Hughes, who owns a musical-instrument shop.

The builders, carpenters and plumbers he has enlisted are mostly family men in their 30s and 40s. They will pay their own fares and stay in the cottage.

Voluntary Service International offers a similar deal, where volunteers pay their fares and get free food and accommodation. It arranges placements with organisations on the ground, at home or around the world.

Marcella Lynch (23), a special-needs assistant at a primary school in Cork, volunteered with VSI last summer. She and a friend went to Bulgaria for three weeks to work at a summer camp for orphans. Lynch visited other care centres and was disturbed by the conditions she found, but enjoyed the experience overall.

"I love working with children, and I love the atmosphere in Eastern Europe," she says. "I'd been to Romania the year before, working with children who had HIV and AIDS. I went with the Romanian Children's Appeal in Waterford. They're a great organisation, and that was more stressful, a harder experience. This time, with VSI, we got more contact with the kids. We were with them all the time, so it was very hard when it came to saying goodbye."

After the camp, they travelled to Bulgaria and northern Greece, which cushioned them a little from culture shock. "We met some lovely characters, but the difference between Bulgaria and Greece was phenomenal. If I'd come home straight from the orphanage, I would have been really low, because I was sad saying goodbye anyway."

Lynch is still in touch with employees and children at the orphanage. Before she left, she gave away many of her clothes. "It's so hard, because you build up a relationship. Coming back to the Celtic Tiger, I felt bad paying big money for clothes. You feel guilty, thinking of what you have and the kids didn't have."

She is taking a year off volunteering, but intends to do it again. "The children are so beautiful and have been through such hardship. When you play with them they go wild. You get a buzz out of it that you won't get on a sun holiday."

Jennifer Lloyd, has caught the same bug. Last summer, she went to Mexico City for four weeks with a group of 11 from Grosvenor Road Baptist Church in Dublin.

Their trip was arranged by Tearfund, a Christian charity. This year, Lloyd will go with the organisation to Uganda for six weeks to lay water pipes.

In Mexico, she taught at a summer school for slum children. After working, she got to see a little of the country. "You go out thinking you are going to help everyone and save the world, but it was the other way round. The people gave us so much," she says. "We were in a very poor area, but the people always looked so well, and were so cheerful, that it was hard to imagine how poor they were."

Mexico City was a distraction, with its trappings of wealth, and she is certain rural Uganda will be very different. Tearfund has organised four days of orientation before she goes.

It will be an expensive trip, so as soon as her exams are done Lloyd will start raising funds. Volunteering means she won't have time for a summer job: she starts her dissertation when she gets back. "I might be sorry when I'm back in college and have no money, but I think it will be worth it," she says. "My dad taught in Kenya after he left college, and I could see myself maybe doing something more long-term."

As for the Ranger Guides who went to India for three weeks in March - Maud Molloy, SinΘad Hynes and Lana Woolley from Galway; Fiona Conway, Catherine Brien and Emer Keogh from Ashbourne, Co Meath, and Nicola Lynam from Enfield, Co Meath - they also returned feeling very committed.

They were led by Claire Davenport, a trainer and facilitator from Enfield who was on her second visit to Bombay. "Guiding develops the girl as a responsible citizen of the world," says Davenport, who has two teenage sons.

The girls came back from India confident, positive and keen to go back as soon as they can. Davenport spent months preparing the girls for the shock of what they would see. But how can you be prepared for the sight of tens of thousands of people living hand-to-mouth on the side of the street?

"I was thrown by the poverty when I went first Next to Sangam was a slum on seven-and-a-half acres, and 10,500 people lived there."

Some of the young Rangers had earned their entire fares, and they had all fund-raised. They came to India bearing gifts and ideas as well as cash donations. They worked with three charities: Sangam, helping people on the adjoining slum; Save Our Souls, a children's village that creates families by encouraging women volunteers to adopt orphans, then supporting them for life; and Ishwari, a rural training centre run by the Medical Missionaries of Mary where women learn skills such as tailoring to support their families.

But the trip wasn't all grind, and they learned about Indian culture, went shopping and on rickshaws and soaked up the atmosphere. They skipped a five-day sightseeing trip and gave the money they saved to the charities instead.

Davenport frets that they didn't bring more money. She intends to return to Bombay when her sons finish school. "The emotional pull is so strong. There's so much to do."

But then she brightens at the memory of the smiles of the orphans at SOS and young women at Ishwari. "We made a difference."

The Tanner Romania Mission is on 042-9321700; Voluntary Service International is on 01-8551011; Tearfund is on 01-4975285; the Irish Girl Guides are on 01-6683898; the Medical Missionaries of Mary are on 01-2887180