Kids Giving Back, a Sydney organisation for volunteers aged six to 18, has been putting children in touch with charities to help out in preparations for Christmas.

Thirteen-year-old Giselle Laszok, of Castlecrag, rounded up a group of friends to pack Christmas hampers for UnitingCare after her mother, Eloise Power, suggested she do some volunteering.

''I wanted Giselle to start giving back,'' Ms Power said. ''She goes to a private school, she lives a fortunate life. She appreciates that but I wanted her to start seeing a different side of life.''

For Giselle, and her friends, the most eye-opening moment was packing hampers for people of no fixed address. ''They'd say 'under the subway' - that's pretty shocking,'' Giselle said.

She said it gave her a greater understanding of how people live.

''We see a lot of sheltered areas where people are pretty wealthy,'' Giselle said. ''It gave us perspective that everyone is not always going to be able to survive.''

More than 1000 school students and their families have volunteered through Kids Giving Back since Ruth Tofler-Riesel and Carole Schlessinger founded the non-profit organisation 18 months ago.

''This is hands-on giving,'' Ms Tofler-Riesel said. ''It's educating kids about other communities. It's breaking down the sense of 'other'.''

In addition to Christmas volunteering, the group puts children in touch with charities, including refugee organisations, year round. It also runs cooking programs in which children cook meals and deliver them to homeless shelters.

Ms Tofler-Riesel said children found volunteering to be a very powerful experience.

''It looks very different to what they're used to,'' she said.

''As soon as they've done the actual task, it's 'wow, that was amazing'. It's the joy of the 'a-ha' moment. Afterwards, they say 'when can we come back?'''