A teacher allowed a schoolgirl to carry out a sex act on him as he drove the school minibus while speaking on his mobile telephone, a court was told yesterday. Andrew Riley, 36, left the girl feeling impressed with his ability to talk to a colleague at the same time, the court was told.

The married father-of-two also took the 18-year-old to hotels, gave her champagne and offered her cocaine before having “amazing” sex with her, Preston Crown Court was told.

Mr Riley, of Lancaster, was head of the sixth form at Baines High School in Poulton-le-Fylde at the time of the alleged incidents.

He denies two charges of an abuse of trust and sexual activity with a child and a single charge of offering to supply cocaine between May and July 2005.

Dennis Watson, for the prosecution, read out pages of Yahoo! instant messages recovered from the girl’s computer.

She had said of the sex act in the minibus: “How funny is it that some Year 12s will be sitting where we had sex and I can’t believe you spoke to [the colleague] on the phone . . . I’m impressed.”

Earlier, the court heard how the two had become close in the summer of 2005.

The teacher told his wife that he was going to a parents’ evening as an excuse for meeting the girl.

The girl “worshipped” her teacher and he referred to her as a “nymphomaniac” who made him feel “damn sexy”.

He said that their liaisons would either end in tears or a “beautiful relationship”.

The court was told how he said to the girl: “You have to promise, in the height of passion you don’t scream ‘Yes Sir! Yes Sir! Because it will put me off what I am doing.”

He told the teenager that cocaine helped him to have the best sex he had experienced.

And the girl told him that the sex was “amazing”.

The court heard how the £36,000-a-year teacher twice took the girl to hotels in Manchester.

He took £200 of cocaine on an overnight school trip and once to the hotel. They took drugs on both occasions, the court heard.

The girl, who cannot be named for legal reasons, said: “I’d gone to the toilet and he’d put the cocaine out in lines on the desk that was in the hotel room. Then Andrew did a line or two.”

When asked if she had taken any, she replied: “Yes.”

The court heard how the teacher was aware that he could get in trouble if their alleged affair was discovered.

He once asked the girl if she was any good at lap dancing and they stripped for each other, the court was told.

She sent him a topless picture of herself over the internet and he sent a video of himself.

“It was a video of him removing his boxers, from the front,” the girl said. “I was showing my breasts while he was showing everything.”

He then sent her a message saying: “Can you believe you have got a video of the head of your year getting his shorts off?”

The girl wrote back saying “Trust me”, to which he replied, “I have to because you could get me locked up”, the court heard.

Mr Riley repeatedly told the girl to delete the videos he had sent, it was claimed.

He wrote: “If this relationship goes **** up, you could batter me.”

When the girl went away to study at university the relationship cooled. She eventually showed her old school a CD of the messages that allegedly passed between her and Mr Riley. The police were called.

Mr Riley did not deny spending nights in a hotel with the girl but denied having sex with her or giving her cocaine.

The trial continues.

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