Taylor Jones of Launceston College in Cornwall, Britain, was told his shaved head was inappropriate and had been given individual tutition for four days until it grows back, reported BBC.
He was told he would be forced to spend break times, lunchtimes and lessons there until his hair grew back.
A 15-year-old who shaved off his hair to raise money for a cancer charity has been removed from his classes for his "extreme hairstyle".
But parents have reacted angrily to the decision, while Taylor's dad accused the school of acting like a "dictatorship".
A schoolboy is being placed in isolation after an "extreme haircut" for charity was deemed to have broken school rules.
He added: "He has been growing it for a while and it had got very unruly and most people said his previous hairstyle was more of an extreme haircut than this is".
But when he arrived back for lessons after the holidays, he said he was nearly immediately sent into isolation for his bald head which teachers said was too "extreme". He said: "He's almost 16 so trying to dictate what length his hair should be is a bit ridiculous".
However, Launceston College upholds their decision in order to maintain discipline for all students.
He wrote on the JustGiving page: "The support I have been getting for this is absolutely incredible, I can not thank anyone enough for what they have done and a huge thank you to everyone who has donated, the amount of money that has been raised is truly awesome".
He added: "It sounds like a dictatorship to me".
The Facebook post on Launceston Notice Board immediately prompted a furious reaction, with people slating the school for punishing the pupil.
Also, dozens of offers poured in to support Taylor's charity fundraising.
"We will not lower [our] expectations but will increase the level of support available to help meet them", it read.
'But apparently the fact that he'd raised over £850 pounds wasn't good enough and before he had even gotten to his first lesson they put him in isolation labeling it an extreme haircut, telling him that he's not able to return to normal lessons until his hair grows back to a more a more suitable length'.