A teenager who stabbed two teachers and a pupil showed school friends the knife before the incident, a court has heard.
Teachers Fiona Elias and Liz Hopkin, and a student, were injured in the attack in April, at Ysgol Dyffryn Aman, also known as Amman Valley School, in Ammanford, Carmarthenshire.
The 14-year-old girl, who cannot be named for legal reasons, previously admitted wounding with intent but has denied attempted murder.
The girl told police: “She said that she was going to stab Ms Elias and she showed us the knife.”
She said the girl “always says stuff we don’t believe” and they did not think she would go through with it.
She added: “I think we all said do not do it.”
The conversation had happened while a group of pupils were sitting in the lower school hall during break time.
The accused was not allowed in the room, which required permission from a head of year.
The girl said Ms Elias had come into the hall and ordered the accused to leave and they went into the corridor to have a conversation.
“You could see from inside the hall, (the girl) she changed, her whole face changed into a different person.”
The student explained that the girl was “disrespectful” and “always arguing” with Ms Elias.
Another pupil, who was in the hall, told police he had also seen the knife.
He said: “She kept saying stuff like: ‘I’m going to get put away for a long time,’ or: ‘You guys won’t see me for a while.’
“I kept looking over at my friends, like: ‘Is this another joke or something?’
“(A boy) sitting beside her said: ‘What are you going to do, then?’
“She just pulled a knife out of a pocket and she went: ‘I’m going to do something which includes a knife.’”
He said he “laughed it off” believing it to be a joke and wanted to distance himself from the conversation.
The jury heard from the girl’s father, who said she had been bullied at the school and alleged someone had attempted to break into their home.
She also asked if their house had been “egged” at one point.
He said: “Yes it did, and there was also evidence that someone had tried breaking in.”
He added: “She would come back in the evening, and she would be upset, she would claim that people had been hitting her on the bus in the back of the head as well as verbal abuse, calling her names – ‘weirdo’ – as well as a whole host of other things.
“Sometimes she would be frightened, she understood the amount of people that didn’t like her, the fact was she felt overwhelmed by the number of people that didn’t like her.”
He agreed that in the months leading up to the event she was “upset, regularly scared and struggling”.
On Thursday, the jury also saw a police interview with another student, who said he had seen the girl being slapped on the back of the head four or five times by the pupil who she went on to stab.
The slapping incident allegedly happened about a month before the stabbing.
William Hughes KC, speaking on behalf of the prosecution, asked the father if the girl had been expelled early in the school year after she had brought a knife in her bag, which he confirmed.
The jury heard that as a condition of returning to school, she was meant to be subject to a bag search every morning.
However, her father said he had failed to carry one out on April 24, with the girl leaving for school before he got up.
The father was shown the item used in the incident, explaining it was a multitool he used for removing hooks from fish and to open paint tin lids.
The trial continues.
