For years they have gradually gone the same way as chalk boards, caning and turkey twizzlers, dwindling out of schools and into the history books. Now blazers are back.

Growing numbers of schools are replacing sweatshirts with the more traditional garb, in response to a demand from pupils to look and feel smarter.

Sales figures from one of Britain’s largest school uniform suppliers show that demand for blazers rose by a third in the last year. Suppliers of more upmarket school garments report a similar surge.

Last week the Conservative Party called for “strict school uniform policies, with blazer, shirt and tie” to improve both discipline and school standards.

Anthony Buckland, marketing director at the school uniform supplier Price & Buckland, which supplies to 2,000 schools, said that there was a widespread retreat from sweatshirt-based uniforms. “What has really struck us, is that the demand for change is coming from the pupils themselves,” he said.

“Pupils and their parents are increasingly aware of the importance of the school image and teachers say it helps improve discipline by making the children take pride in their appearance and in their school.”

Many schools have changed traditional blazer design to suit changing fashions, adding a coloured trim or piping around the edge of the lapels.

Mr Buckland said that a change in the way blazers were made may also be behind the rise in sales. New fabrics meant that blazers could be low in price (prices start at £29), machine-washable and “virtually bullet-proof”.

The popularity of the blazer is growing at the other end of the market, too. Barnard Bunting, the managing director of Perry’s Uniform, which supplies uniforms for independent schools, said that woollen blazers were the biggest growth area for his company.

Perry’s blazers are 90 per cent wool, have to be dry-cleaned and start at £69. They are most definitely not the sort of garment you would want to use as a goal post in the playground, Mr Bunting said.

Independent schools increasingly viewed uniforms as a key marketing tool, to help to attract parents and pupils in an increasingly competitive marketplace. “A blazer can create a very strong brand image for the school,” Mr Bunting said.

Joyce Daly, the vice-chairwoman of the Schoolwear Association, which represents manufacturers and suppliers, said: “Research we commissioned earlier this year with Oxford Brookes showed that pupils enjoy the sense of pride they get from wearing a smart uniform and the smarter the better.”

Carol Jones, head of Fulham Cross School, a girls’ state secondary in West London, said that results had improved since a blazer was introduced as part of the uniform. The blazer – which is black with a pink trim and a matching logo designed by the children – was chosen by the school council in consultation with all pupils. “As soon as I arrived at the school, the girls came to me and said they wanted a smart new uniform. They said the old one – a black and red sweatshirt – made them feel scruffy and felt too much like a primary school uniform,” Ms Jones said.

“They feel an incredible sense of pride in the new uniform – they are walking taller and it has helped raise school standards by making them feel that this is a successful school.”

Ms Jones said that since the school started to phase in the new uniform, GCSE passes had jumped from 42 per cent to 53 per cent. Hiba El-Chikhe, 15, a member of the school council at Fulham Cross, said: “We all really loved the idea of having a blazer. We felt that if we were dressed smarter, then we would work harder. If you feel more confident in yourself, that reflects in your behaviour.”

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