A woman told a court she reported an alleged sex attack by agricultural engineer Robert-Hayes Danson to the child protection officer at her school.
The woman, who cannot be identified, also wrote to the teen support charity Talkwize.
Giving evidence at Preston Crown Court, the third woman to claim to have been sexually assaulted by Danson said she also witnessed the defendant kissing another of the complainants.
She said following that incident she lost trust in married Danson and avoided him and the other alleged victim as she did not want to have to ask them about what she had seen.
But when she was 14 years old the woman said Danson assaulted her sexually.
After the alleged incident the woman wrote two letters – one to her teacher and the other to Talkwize.
In the letter to the charity, the youngster wrote: “I need some help but I don’t want my mum and family to know.
“I have spoken to a teacher at school but she doesn’t seem to care any more.”
However the woman said she does recall being taken out of class to discuss the allegations.
When she was younger she said Danson would “play fight” with her, which she thought was innocent but she said she later wondered if it was as innocent as she had thought.
Danson, 46, of Birch Avenue, Newton-with-Scales, denies 11 counts of indecent assault and two counts of indecency with a child and the trial continues.