Three teenagers are sleeping rough in an Oxford graveyard to experience being homeless for a night.

Cherwell School students Lucy Bale, 15, Naomi Zetter, 14, and Joanna Furtado, 15, are braving the cold, damp and creepy location next week, to give themselves an idea of what homeless people suffer every day.

The girls will build a makeshift shelter using cardboard and wood and spend the night in sleeping bags outside St Nicholas Church in Old Marston.

Lucy's father, Jeremy, will be helping them and staying overnight to make sure they are safe.

Miss Furtado said: "I used to know someone who was homeless. They manged to find housing as a result of a charity, so I know how much they can do.

"I'm glad we are doing it, but I think it's going to be scary and really cold."

The girls came up with the idea as they were researching a school citizenship project - and decided to raise sponsorship money for Oxford homeless shelter Gatehouse in the process Miss Bale said: "Lots of other groups in the year are doing projects about global issues, but we wanted to do something about homelessness because it's such a big thing in Oxford.

"When I see someone on the street, I feel guilty, and that I should be doing something to help."

The girls have already been promised almost £100 in sponsorship from friends, family and classmates, but they hope to raise more.

Miss Zetter said: "We just felt it was something really important to do, as we are all interested in social issues. But we are nervous about the night itself."

After their night in the open, the girls will give up some time to Gatehouse, by doing adminstration in the offices.

Andrew Smith, project director of Gatehouse, said: "It's brilliant to have help from people so young. The girls certainly are very resourceful.

"If you are under 18, it's not possible to volunteer by serving food to guests at Gatehouse, but there are many other ways of helping out by raising money.

"It's good for people to know that they can help without even stepping foot in the shelter. Lots of older people bake cakes or make soup for us to serve."

Gatehouse is a shelter for homeless people aged over 25, based in Northgate Hall, St Michael's Street. The service is open from 5pm to 7pm from Tuesday to Saturday and 3pm to 5pm on Sundays, providing hot drinks, sandwiches, cake and soup in winter for free.

For more information, visit www.oxfordgatehouse.org