School uniform is not about education, it is about control. That is the view of University of Stirling professor Mark Priestley, a leading expert on curriculum studies. School uniform has also come under fire for wasting the time of the senior management teams that have to deal with infractions; for suppressing individuality and creativity; and for being a burden on disadvantaged families.

MSPs investigating the effects of poverty on learning have heard that “unnecessary fripperies” on elaborate school uniforms are pricing out disadvantaged pupils - a trend that led to much criticism online when it was reported by Tes Scotland. In one school, the cost of a blazer badge and piping alone was reportedly £40.

However, support for uniform remains widespread among teachers and heads. A snap Twitter poll by Tes Scotland asking “Is school uniform a good idea?” elicited an 84 per cent response in support of uniform from the 372 people surveyed.

Uniform is an emotive issue, says Donald Macdonald, head of one of the few Scottish state schools where pupils are not expected to wear one: James Gillespie’s High School in Edinburgh. A 2015 survey of parents and pupils by his school asking whether it should introduce a more formal dress code attracted nearly 2,000 responses - and many doubters. Ultimately, the school chose to keep its more casual dress code.

But in his previous school, Macdonald introduced a uniform as part of an attainment drive. The school was underperforming and he wanted pupils to wear uniform as a means of changing the culture and attitudes to work.

“In that context, I felt that youngsters being prepared for a business day, for a working day, was important when it came to changing the ethos of the school,” he says.

Other teachers echo this sentiment, but Priestley, who is deputy dean of his university’s social sciences faculty, says: “Claims that uniform improves school ethos have little basis in research and can be seen as little more than assertions.”

The Education Endowment Foundation similarly finds that research suggests uniform by itself has “very low or no impact” on attainment, and it is a similar case for behaviour and attendance.

‘Post-hoc justification’

Priestley - who is not against dress codes or more “functional” uniforms - also dismisses another popular argument: that uniform prevents a “fashion arms race”, as one teacher puts it. He says: “This argument has always seemed to me to be a post-hoc justification in schools that already have uniforms.”

Headteacher Stuart Clark, however, says his main motivation for having a uniform is that it creates “a level playing field” and removes pressure on families to buy clothes that “meet the expectations of their child’s peers”. This year, his school, Port Glasgow High in Inverclyde, introduced a new blazer, complete with piping, but most senior pupils who wear one hire it for just £5 (see box, below).

Macdonald, however, predicts that we are on the cusp of a more relaxed era. Education is cyclical, he says, and he expects that within the decade things will “swing towards a non-uniform approach”. He adds: “With increasing awareness of personalisation and individual rights, it will become much harder for schools to insist youngsters dress in a certain way.”

Until that happens, Amanda Corrigan - director of student experience at the University of Strathclyde School of Education - is calling for schools to ensure mandatory uniform does not cost more than the clothing grant that less well-off families receive.

She says: “Schools need to make decisions about uniform based on the needs of all children in the school, using the clothing grant as a point of reference.”