Up to 150 girls were sent home from school on their first day back after summer holidays on Friday, for wearing skirts that were 'too short'.
The female students from Tring School were reportedly either picked up by their parents - or placed in seclusion - after teachers told them their uniforms were inappropriate on Friday.
The girls were reportedly pulled aside by teachers if their skirt hem did not reach their knees.
The school's uniform policy states that skirts must be 'knee length and of a pleated design'.
Many parents were outraged at the decision to send their daughters home - but the school was also unhappy about the response by parents to vent their frustrations on social media and to the press.
Mum Lisa Thompson had to take her 13 year-old daughter to Tesco to buy her some trousers after her daughter was told her skirt was inappropriate.
Another mum of a 13-year-old girl said that her understanding was that 150 girls were sent home from school for having skirts deemed by teachers as too short.
Headteacher of Tring School - Mrs Collings - explained in a statement to ITV News that the school believes looking smart and professional is important.
The school had previously communicated to parents in July that students who were "incorrectly dressed" would be told to improve their uniforms to the necessary standard before attending lessons.
Tring School has around 1,505 pupils aged 11 to 18.