A 12-year-old girl has been banned from class after shaving her head for charity - because the drastic style was against school rules. Charlotte Duggan raised £1,000 to have her hair chopped off for Breast Cancer Campaign after being inspired by her own grandmother's successful battle with the deadly disease nine years ago.javascript:openNewWindow('pix.php',%20'PhotoGallery','900','700'); She returned to school in Basingstoke, Hampshire expecting to be praised for her selflessness, but instead was left 'upset' and 'humiliated' when teachers banished her into isolation for two days. Charlotte was also prohibited from mixing with her classmates and going out at lunch and breaktimes - with teachers at Cranbourne Business and Enterprise College allowing her only a brief trip to the canteen. She decided to undergo the radical image overhaul at the beginning of August, when schools were on annual summer holiday. The young fundraiser, who also had the Breast Cancer Campaign's iconic yellow ribbon shaped into her shorn hair, was devastated by the school's reaction. She said: 'I only decided to shave my head at the beginning of August so I could not have asked the school for permission. 'Isolation is supposed to be for bad behaviour. I was upset and I don’t know how it will affect my education.' Charlotte's mum, Kerry Duggan, 31, has also been left furious by the way her daughter's good deed was repaid. She adds: 'I couldn’t believe it when she told me what had happened. She should be proud of what she has done. She should be able to hold her head up high. 'I think it’s absolutely ridiculous that they made her feel like she had done something wrong.' However, the school's headmistress Betty Elkins insists she asked Mr and Mrs Duggan if the ribbon pattern could be covered up during school time, which they refused. Ms Elkins also said that Charlotte was allowed to concentrate on her fundraising while in isolation. She explained: 'We asked if Charlotte would be able to cover up the pattern but that wasn’t something her parents thought was acceptable. 'When Charlotte was in isolation, she was working on an assembly about her fundraising which she will be presenting to the whole school. This will hopefully mean she will raise even more money.' All pupils received a letter before the school holidays reminding them about appropriate hairstyles.