Kandice Barber, 35, was found guilty by a majority of 10 to two of one count of sexual communication with a child and one of causing a child to watch a sexual act by a person in a position of trust.
he was acquitted at Aylesbury Crown Court of causing or inciting a child to engage in sexual activities while in a position of trust.
Jurors continued to deliberate on the remaining three charges of causing or inciting a child aged under 16 to engage in a sexual act, before being dismissed after not reaching a verdict on Tuesday afternoon. A retrial is expected to take place in January.
The allegations are said to have taken place between September and October 2018.
Barber denied all charges against her.
Aylesbury Crown Court was told Barber added herself to the pupil’s Snapchat at a sports presentation in September 2018, before having sex with him in a field the following month.
Jurors heard how the boy denied rumours of an affair with Barber in January 2019, allegedly because she said she could be pregnant with his baby.
He later told the head what allegedly happened in March 2019, and claimed Barber had picked him up and had sex with him after school.
Barber’s defence lawyer Nadia Chbat suggested the boy made a false account on Snapchat and invented a conversation he then took screenshots of. The pupil denied this, and said he was not “obsessed” with Barber.
The student said Barber told him she “was going to bring me down with her” if he talked about the affair.
Jurors heard that, in a statement to police, a social worker said Barber told her she “let her guard down” and sent a topless picture to the boy.
The court also heard that Barber searched “alibi” and “having an affair” online, which the teacher insisted were film references, and “secluded area”, which she said was in order to take a dog for a walk.
Barber’s husband Daniel said he “kind of guessed” why she was arrested in March 2019, and told the court the couple had been trying for a baby at the time the alleged offences are said to have taken place.
Daniel Barber, who accompanied his wife in court along with her mother Dawn Green as the verdicts were given, told jurors she was his “rock” and denied their relationship was going through a bad patch at the time of the offences.
Barber said she gave her number to the pupil so he could speak to her about an issue at school, though she was not supposed to contact pupils outside of school without permission from the head.
“It is something I am incredibly embarrassed about, I know it was the wrong thing to do but I had good intentions in doing it,” Barber, of Wendover, said.
She told the court the pupil would message her persistently and she became uncomfortable with the communication.
In November 2018, she went off school for two weeks after suffering an ectopic pregnancy. Barber said she never told the student the baby could be his, but the fact she lost a baby was known at the school.
The topless photos that circulated around the school were leaked because a folder in her Snapchat was hacked, Barber said.
The court heard she sent a message to the pupil telling him to “delete everything – don’t want to get in any trouble”.
After she refused to have further contact with him, she told jurors he sent a message that said: “Watch what’s going to happen, you’re going to lose your job, you’re going to lose your family.”
The student denied sending this.
The jury of seven women and five men delivered their verdicts on Tuesday after deliberating for more than 10 hours.