A teacher has been told he faces time behind bars after French-kissing a girl of 14 and questioning embarrassed pupils about their sex lives.

Keith Ogunsola, 44, a married father from Banstead, grabbed the stunned teenager in his office and put his tongue into her mouth, the court was told.

The science master, who taught in Carshalton and Essex, also asked girls in a chemistry revision class if they had performed oral sex, the court heard.

At Snaresbrook Crown Court on Friday, a jury deliberated for three hours before unanimously convicting him of sexual assault.

Judge Martyn Zeidman, QC, told Ogunsola: “You have committed a huge breach of trust.

“You have taken advantage of that girl and you have behaved disgracefully. You’re facing an immediate prison sentence.”

The judge requested pre-sentence reports and a victim impact statement as he bailed Ogunsola for sentencing on August 28.

Prosecutors are to seek an order banning the Nigerian-born teacher, of Chipstead Way, from working with youngsters in future.

The court heard Ogunsola had been warned about his conduct by the headteacher of the Carshalton school.

He left this school in 2001, later taking up a teaching post in Ilford, Essex, where he molested the 14-year-old pupil on February 27 last year.

The teenager told specially trained police officers that Ogunsola told her to dump her boyfriend and would become jealous of pupils’ boyfriends.

Reliving her ordeal in a video played to jurors, she said: “He pulled me close and then kissed me and put his tongue in my mouth.

“I pushed him away. He pulled me really close. He was holding my wrists and he kissed me again.”

The girl, who was “shocked” by Ogunsola’s advances and simply “froze”, said he then asked her: “Aren’t you supposed to be my Valentine?”

Ogunsola, was acquitted of two separate counts of indecent assault at the Carshalton school and an attempted sexual assault.