A girl was put into isolation at her school after she had her head shaved for charity.
Niamh Baldwin, 14, was taken out of classes by Mounts Bay Academy in Penzance because of the haircut.
She had donated her hair to the Little Princess Trust, which makes wigs for ill children suffering from hair loss.
The school said her appearance was "confusing and upsetting" to students, and it was unaware the charity event was taking place.
Anneka Baldwin, Niamh's mother, said her child's hair style should not decide whether she can be in class.
"I am so upset that the school has made her feel so low," she said, branding the decision a form of "discrimination".
After being put in isolation on Thursday, Niamh did not attend school on Friday due to being upset at the prospect of being put in isolation again, her mother said.
On Monday her hair was judged to have grown enough for her to be put back into normal classes.
"Although Niamh is back to classes I still feel like the positive and amazing deed she did has been dampened and not praised as it should have been," Mrs Baldwin said.
She added she was "so proud" of her daughter, and disagreed with the school's rules on hair length.
Mounts Bay Academy vice principal Les Hall said Niamh was removed "for a short time" as her appearance was "upsetting and confusing to a number of students and staff", but was not excluded.
He added the school had not been made aware about the charity head shave, and the reasons behind the hair cut "were unclear at the time".
"Niamh was soon after returned to her normal lessons where she is currently studying successfully," Mr Hall said.