A supply teacher who secretly filmed pupils fighting, swearing at her and disrupting classes for a television documentary was found guilty of unacceptable professional conduct yesterday and suspended from teaching for a year.

Angela Mason, 60, went undercover at several schools in London and around Newcastle upon Tyne in 2004 and 2005 to film the documentary Classroom Chaos for Five, the television channel.

Using a camera hidden in her hand-bag and shirt buttonhole, she recorded a number of incidents of pupils disrupting her lessons, including children searching for pornography on their school computers.

Mrs Mason, who left teaching more than 30 years ago to work in broadcasting, admitted carrying out the filming, but denied that it amounted to unacceptable professional conduct, arguing that she was acting in the public interest.

At a hearing in Birmingham the General Teaching Council, the body that regulates the profession in England, ruled that the public-interest defence was not strong enough to justify the breach of trust implicit in the secret filming.

In its findings the council committee noted that it had watched film of Mrs Mason’s lessons, and that she had lacked the necessary skills to manage the behaviour of her pupils.

“We saw numerous examples of poor practice, including failure to model respectful behaviour to pupils, inappropriate comments to pupils and indiscriminate negative comments to a whole class in response to examples of bad behaviour by individual pupils,” they wrote.

The committee acknowledged that Mrs Mason was a journalist and, from that perspective, her decision to film the classes “may have been justified”. It added that it had been forced to consider her behaviour as a teacher.

“We accept that Mrs Mason was well intentioned in her actions and, that, in this case, no lasting damage has been done to pupils or schools. But the principle of secret filming is a breach of trust on the part of the registered teacher,” the committee stated. “We are conscious that Mrs Mason has neither shown insight nor demonstrated any understanding of the significance of this.”

Mrs Mason, a mother of two, said that she had no regrets about the covert filming.

“Teachers and parents know that a minority of pupils are blighting the opportunities of a generation,” she said. “My filming revealed that in a clear and direct way, and I have been punished for it. The GTC has done nothing to help pupils or teachers by sanctioning me in this way.”

Teaching unions welcomed the suspension. Steve Sinnott, general secretary of the National Union of Teachers, said that pupils and parents had a right to be able to trust their teachers. “Mrs Mason betrayed that trust. Her behaviour was unacceptable,” he said.

Classroom chaos

I’ve got just as much right as you to say what I want. I’ve got a right to speak up for myself

A 12-year-old in a maths class who was told off for swearing

Another scene showed a teenage boy telling the teacher, who taught under the pseudonym of Sylvia Thomas, as she tried to control the class to “**** off”

During break time her classroom was vandalised, with windows smashed and glass thrown around the room, books destroyed and desks overturned

Boys openly used mobiles to download pornography, access obscene websites on school computers and make serious sexual suggestions

One pupil accused the teacher of hitting him, and threatening to report her to the police and sue her

In another lesson, when the petite, middle-aged teacher, called for the raucous class to be quiet, a boy’s voice is heard above the din, shouting out: S**k me off, miss"

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