Mary Orme, who has taught for 25 years, was punched and had her face cut by Martha Philbert at the end of school registration.

Ms Philbert, 37, from New Cross, south-east London, admitted actual bodily harm to Mrs Orme, who at the time of the attack was head of English at St Joseph’s Academy, an 11-16 Catholic boys’ comprehensive in Blackheath. Ms Philbert was sentenced at Blackfriars Crown Court last Friday.

“Teachers ... have a right to be safe,” said Mrs Orme. “This woman did what she did because she thought nothing would happen to her. Parents have to understand that they can’t come into schools and assault teachers... I followed this case through for the sake of my colleagues.”

Mrs Orme, 54, reprimanded Ms Philbert’s 14-year-old son for truancy in March. When his banned mobile phone rang, she asked him to hand it over. He refused so she sent him out of the class. He contacted his mother. “He had his mobile and she had her mobile and he must have guided her in,” said Mrs Orme.

Mrs Orme says Ms Philbert burst through the classroom door and punched her on the upper arm. She then dug her nails into Mrs Orme’s face, causing bleeding, before running out of school.

“I offered no resistance because I was conscious there was a class of 25 boys watching. The last thing they should see was two adults brawling,” said Mrs Orme.

Mrs Orme continued teaching but collapsed two months later through stress. She is not currently teaching.

In July a Sheffield mother-of-three was jailed for three months for punching a pregnant teacher in a row over the cost of a school trip.

In May 2001 two parents were imprisoned for nine months after holding a Watford head hostage in her office. Tough new powers against trouble-making pupils and parents are expected in next week’s Queen’s Speech.

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