A drama teacher with a 30-year career behind her is facing the sack after being convicted of smacking a boy around the head for chatting during lessons.
The child said he had previously been caught talking, but insisted he had not been doing so when Ms Greening lashed out.
His outraged parents complained about the incident, and the school contacted the police, leading to Ms Greening being charged.
The teacher was found guilty of common assault at Sandwell magistrates' court, and sentenced to a six-month community order.
The court was told that the pupil was shocked by Ms Greening's actions but unhurt, and had told the police that the slap 'didn't hurt'.
Ms Greening pleaded not guilty to the charge, but magistrates heard she had been reprimanded previously for her conduct.
Laura Culley, defending, said the teacher did not accept that the incident happened 'intentionally or otherwise'.
Following the court case, Ian Binnie, the headmaster at Alexandra High - which has around 1,400 pupils on its roll - said that the school's disciplinary procedures were under way.
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