Teacher Wally Knight is having to give up selling sweets at break time in aid of charity because of a new nationwide healthy schools policy.

In the past six years, Mr Knight has raised more than £15,000 for Cancer Research UK through sales at St John’s School, Marlborough.

Initially he sold individual sweets but now sells them in bags to avoid dealing with small change.

The 60-year-old teacher of French and German has kept meticulous records of what he paid for the sweets, returning the exact cost to his own pocket, and ensuring all profit has gone to the charity.

Mr Knight, who has taught at St John’s for 17 years, said: “I have raised over £15,000 since I started and it has been gift-aided, so effectively it mounts up to £20,000.”

He said he was disappointed the healthy foods charter meant he could no longer sell sweets to the students, but he is thinking up some alternative fundraising ideas.

Last year he made £3,600 for the charity and this year he had set his sights on making a profit of £4,000 until the school introduced its no-sweets policy as part of a national healthy schools drive.

However, St John’s head Patrick Hazlewood said he would ensure Mr Knight reached his target for the year by giving him part of the proceeds of two non-uniform days to add to his collection.

Dr Hazlewood said he encouraged charity fundraising at St John’s and praised Mr Knight for his work.

He said: “He has raised a huge amount and done a fantastic job.”

The head teacher said the school, in common with most other schools, had introduced a healthy foods policy and that the sale of sweets had to be discontinued.

“We have agreed Mr Knight can have some of the proceeds of our non-uniform days,” said the head, adding that these raised between £1,500 and £1,800 each year.

Dr Hazlewood said: “In the past year, St John’s raised nearly £9,000 for charitable causes including Afghan Heroes, Ten for Ten, Young Carers Wiltshire, UNICEF, John Radcliffe Hospital, New Life, libraries in Zambia and World Aids Day.

“We are very proud of our students’ efforts and the commitment they show to helping and supporting other people around the world.”

Mr Knight said he started the enterprise because so many people had lost friends or relatives to cancer. His mother-in-law died from cancer three years ago.

He can, however, continue selling pens and pencils to children.