They highlight interview turn-offs ranging from personal hygiene problems and poor appearance to spelling mistakes on application forms and pompous, rambling letters written in odd-coloured pens.

More than a quarter of heads interviewed felt the quality of applicants for teaching posts last year was worse than in 2001, while 51 per cent said it was the same.

John Dunford, Secondary Heads Association general secretary, said: “When you interview people you are always thinking about what this person is going to be like in front of a classroom. If they have not had a bath for a week it is not going to encourage the children to get on with their work.”

The faux pas are revealed in a survey of 167 heads by supply teacher agency Select Education.

Complaints included candidates who had no knowledge of the school they were applying to, lacked character or confidence and failed to show they liked children.

The annual True Time and Cost of Teacher Recruitment survey also revealed 60 per cent of schools had vacancies for permanent teaching staff at the start of this term.

More than a third of heads said they spent more than a week recruiting a teacher.

Select Education calculated the total cost of hiring a new teacher was more than pound;4,000, once all the staff, management and governors’ time, advertising and other costs were taken into account. David Rose, spokesman for Select, said the survey showed the advantages of finding permanent staff through an agency who charge up to pound;4,000.

“We make sure they know how to fill in an application form - and how they should dress,” he said.