Students at Prestwich Arts College were sent home to change after turning up to school in incorrect uniform.
It is understood a number of pupils were pulled up at the school gates for wearing footwear, clothing, piercings and hairstyles that went against college's standards.
Most were taken into the school to 'rectify' their uniform, however, five children ended up having to go home to get sorted.
Prestwich Arts College headteacher Rachel Evans said the parents of these students were aware, and that they were all back in class shortly afterwards.
Over the summer, several letters have been sent home reminding families about uniform standards, as well as posts on social media.
Miss Evans said in a statement: "Our uniform expectations were set out very clearly to all pupils before we broke up for the summer holidays.
"We also sent out a number of letters to parents, at the end of last term and during the holiday, to reiterate our expectations.
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"This morning, we welcomed pupils at the gate as they arrived and those who did not have the correct uniform, were brought into school to rectify their attire.
"As a school, we have purchased a lot of uniform, to support parents and pupils in ensuring that they are not financially disadvantaged, whilst they try to meet school expectations.
"Pupils have also been given uniform cards, which give them a grace period, during which they can rectify their uniform.
"No more than 5 pupils have actually gone home today, to rectify their uniform and this was agreed in conjunction with the parents of these children.
"These pupils quickly returned to school, wearing the correct uniform and are all in lesson.
"We believe it is important that our pupils have high expectations about how they present themselves.
"It was lovely to see the overall majority of pupils looking very smart this morning and keen to learn.
"We would like to thank the vast majority of parents, who have supported us in ensuring this is the case.
"We would also like to thank the parents who contacted us during the summer, to ensure their child would meet our uniform expectations upon their return."
