A 15-year-old schoolgirl was put in isolation after turning up to class with dyed ginger hair.
Shaunni Barker coloured her blonde locks red but was stunned when she was told by teachers her hair broke school policy.
She was removed from classes and she was ordered to do her school work in an isolation room at Skegness Academy, Lincolnshire, until she washed the dye out.
But her furious mum Sharon, 42, has refused and is demanding her daughter is allowed back into class.
She said: "I've taken her home now because she will get no work done without her teachers to help her.
"Shaunni is a good and studious student. Ginger is a natural colour really. It's disgusting a student can be sent home or put isolation because of the colour of her hair.
"How does the colour affect how you learn? She's a good kid.
"I might be able to understand it better if she turned up to school with pink hair but ginger, or deep red is a recognised colour."
Shaunni was put into isolation when she turned up at the academy, which teaches 1,190 pupils aged 11-19, on Monday. But the school has defended the policy on hair colour.
Executive Principal Emma Hadley said: "Our pupils are ambassadors for the Academy and we expect them to represent us in the correct manner.
"We want our pupils to present themselves smartly as we believe that the self-discipline this requires is an important lesson to learn as pupils will find that there is often a dress code in most places of work.
"We provide very clear guidance to parents in our prospectus."
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