A supply teacher who secretly filmed unruly behaviour in the classroom for a Channel 5 documentary misused her position, a tribunal has heard.
Mrs Mason used a hidden camera in her handbag
The General Teaching Council heard how supply teacher Angela Mason filmed pupils disrupting lessons at schools in London and north-east England.
Mrs Mason, from London, is also accused of failing to promote the children's welfare by managing their behaviour.
She denies this and a charge of unacceptable professional conduct.
She admits the secret filming with a camera hidden in her handbag for the programme Classroom Chaos, but claims she was acting in the public interest.
Presenting officer Bradley Albuery told a hearing of the GTC, the body which regulates teachers, that by filming teachers and pupils without their knowledge or consent she had "misused her professional position".
"She was there not as a broadcaster but as a teacher. All of her attention should have been directed at the education of the children," he told the hearing in Birmingham.
By going into schools with a hidden camera, she had created a conflict of interest, he argued.
"The fact that she took a camera into the classroom shows that her agenda was not as it should have been: focused wholly on the needs of the children."
Those filmed for the programme reacted angrily to it.
One student who claimed he could be identified from the footage said he felt "embarrassed and humiliated", the hearing heard.
During the documentary, which was shown to the tribunal, one boy tells Mrs Mason to "take a nap" when she attempts to restore order to the class.
Another is shown using a school computer to look for pornographic images on the internet.
Mrs Mason originally left teaching in the 1970s to work in educational broadcasting.
But the tribunal heard she had enrolled with two supply teaching firms to take part in the documentary.
Clive Rawlings, appearing for Mrs Mason, said she had embarked upon a "responsible and reasonable" piece of journalism, and her actions contributed to the debate on classroom behaviour.
Mrs Mason as a teacher 30 years ago
"Angela Mason's actions, which she is being castigated for, were in the public interest in its broadest sense."
He added: "Angela Mason is merely the messenger, and we submit that you should not shoot the messenger.
"You should send out a message that teachers should be given back the classrooms."
Although Mrs Mason no longer worked as a teacher, the allegations were an attempt to "besmirch her professional character", Mr Rawlings said.
If the case against her is proven, she could be permanently banned from teaching.
Speaking after the hearing, Mrs Mason said she was fighting the allegations because she still felt passionately about the profession she left 30 years ago.
"I believe there is a major public policy issue to do with pupils in classrooms and poor behaviour.
"I'm standing up for the supply teachers and other teachers who have to endure this every day."
The tribunal hearing continues.