These girls raised £270 for Helen House hospice in Oxford by camping outdoors for a week in 1985.
Charlotte Brown, left, and Debbie Shouler, both 11 and from Wendlebury, near Bicester, started by washing cars and earning £30 to buy a tent.
They set up the tent in a field at Elm Tree Farm, owned by Debbie’s father, Frank Shouler, and camped for a week, looking after themselves and cooking all their meals.
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Debbie, a pupil at Oxford High School, said: “We thought it would be fun to go camping.”
Charlotte, who was due to start at Bicester School, said the week under canvas had been fun, but very wet.
“But we are glad we did it and grateful to all the people who gave money.”
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