Teachers have gone on strike over concerns about violence and threats from pupils.
Some staff at Starbank Secondary School in Birmingham said they received little support from bosses in confronting the badly behaved pupils.
A teaching union says a “knife audit” needs to take place, along with risk assessments for teachers and a behaviour policy for pupils.
The school has been contacted for a comment.
Birmingham City Council said “conversations are ongoing with trade unions over concerns raised” and that “suitable provision has been made to ensure that lessons will continue” during the two-day strike.
Paul Nesbitt, National Association of Schoolmasters and Union of Women Teachers (NASUWT) national executive member for the West Midlands, said the union had been negotiating with the school for some time.
He also said staff had informed him about violence from pupils and threats.
He said: “Sufficient practical steps have not been taken to ensure poor behaviour is addressed and that teachers are supported in maintaining good order in the classroom”.
He added that teachers at the school on Hob Moor Road had been left with “little choice” but to embark on two days of planned action.
A safeguarding review has been carried out by the local authority, the union said, and staff are awaiting the results.
“We want training for members on how to deal with these situations and a knife audit”, Mr Nesbitt said.
“We’ve asked the school to come up with a behaviour policy which looks after children and our members.”
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