Erin Hebblewhite, 29, groomed the girl with flirty text messages before they launched into an “intense and passionate” affair.
The teenager had her first kiss with Hebblewhite, lost her virginity to the older woman, and told police she felt pressured into posing for naked pictures.
The relationship was exposed when the girl’s family – concerned about alarming changes in her appearance and behaviour – confiscated her phone and found messages from Hebblewhite.
Sentencing her to two years in prison on Tuesday, Judge Neil Sanders said Hebblewhite had left the girl stressed and anxious, contemplating suicide, and struggling to form romantic relationships.
“I consider the appropriate punishment can only be achieved by immediate custody”, he said, dismissing pleas for a suspended sentence.
Hebblewhite – described in court as “intelligent and talented” - wiped away tears as the sentence was passed down, as her new partner of 18-months sobbed in the public gallery.
In a letter to the judge, she admitted being “truly blind to the negative impact” on the girl, and conceding: “I can now see the environment I had created – one of pressure and premature sexualisation.
“The damage has been done, I can’t reverse it, no matter how deeply I might want to.”
Hebblewhite was nominated for a sports teacher of the year award.
Prosecutor Fiona Ryan said Hebblewhite, an Australian national, swapped phone numbers with the girl who she had picked out as a “favourite”.
“She sent her a text asking if she liked her, and a flirtatious series of messages began in which the teacher made clear she was attracted to (her)”, said the prosecutor.
Ms Ryan described a series of sexual encounters initiated by Hebblewhite, including the girl’s first experience of sex in the toilets of a restaurant.
“She felt she had given in to pressure to behave more and more sexually”, she said. “The defendant viewed her reluctance as ‘playing hard to get’ but in fact it was because she was inexperienced and nervous.”
Hebblewhite broke up with her current partner and started inviting the girl to her home, the court heard.
“She often went to the defendant’s home to have sex”, said Ms Ryan. “Photographs were taken of the two of them together. (The girl) later said she didn’t really want photos to be taken but felt pressured into making Ms Hebblewhite happy.”
She added Hebblewhite had once tried to pressure the girl into having sex in the toilets of a Primark, but the teenager refused.
“This relationship only came to an end because (the girl)’s family found out and that triggered police being notified”, said Ms Ryan.
“The defendant was concerned for her own position and begged her to delete messages and erase her phone, which was partially successful.”
Love letters describing “intense and passionate sex” were recovered by police, as well as around 400 images and messages between Hebblewhite and the girl.
Bethan Rogers, mitigating, said the criminal charges have “destroyed” Hebblewhite’s promising teaching career. She has since retrained in coding and web development, and has advised Google on educational teaching programmes.
“She is a good person who made a truly terrible, egregious mistake for which she will pay for years to come”, she added.
Hebblewhite, who now lives in Brighton, pleaded guilty to four counts of sexual activity with a child, sexual activity in the presence of a child, and two charges of making indecent photographs.
She is banned from contacting the teenager for the next ten years and will be under a Sexual Harm Prevention Order to stop her working with children or being alone with them.
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