Holderness Academy took the action after a Year 7 pupil turned up in the Asda black dress, which was almost identical in all but price to the equivalent sold at the official supplier, Rawcliffes.
The supermarket sells a twin pair of black dresses for £14 whereas the approved dress would set families back £17.99 to £21.99 from the more upmarket retailer, Hull Live has reported.
A parent told the website: “I had to replace shoes because they had a gold trim. My daughter was subjected to a 50-minute line-up on the playground with all the other Year 7s in blazing sun on Tuesday, while the assistant head and other teachers went up and down the lines inspecting them.
“There’s children having buckles cut off their shoes by teachers, put in isolation for wearing a belt, and being told they can’t wear a skirt bought from Asda despite it being identical to the one from Rawcliffes school shop.”
Parents are also required by the school to fork out £34 for a girl’s blazer, up to £21 for a twin pack of the girls’ white blouse, £5.99 for a two pack of tights, and £5.50 for the school tie. Although much cheaper supermarket equivalents are available, the school’s academy trust has stood by its uniform policy.
“The start of the academic year is a key period in which standards and expectations are set,” a statement, reprinted by Hull Live, read.
“We work respectfully with our learners to support good habits and adherence to key policies; this is in the best interest of all members of the school community.
“Our schools’ uniform expectations foster equality and encourage a sense of pride and belonging in the community.
“We are working through a small number of concerns that have been raised by parents and will continue to work with them to overcome any barriers.”
The Consortium Academy Trust added that parents should get in touch over difficulties involving the uniform.
A Department for Education Spokesperson said: “We have been absolutely clear that uniform should be affordable and costs for parents should be kept down by enabling them to choose high-street and unbranded options.
"Our statutory guidance is that cost and value for money for parents should be the most important consideration by schools when deciding how to source uniform and we expect schools to follow this."