Two Rochester Grammar School pupils have been excluded for 20 days after crushed nuts were found in the classroom of a teacher, who has a severe allergy.

Both girls strongly deny claims they were responsible - with one of them even taking a lie detector test to prove so.

The incident happened at the Maidstone Road school last week.

Poppy Jeffrey went to speak to Alexandra and her dad

Alexandra McDonald said: “I’m gutted. When I was told I was going to be excluded I was shocked, I couldn’t speak. I’ve always wanted to be a teacher but this makes me think it’s not something I want to do, if this can happen to an innocent person. It definitely was not me.

“I loved school and the environment, I thought all the teachers were really friendly, understanding and there to help.”

The 16-year-old studies geography, PE and religious studies and hopes to attend the University of Kent.

However, the exclusion means she will now sit her A-level mocks at a different school in isolation.

According to her father, Peter McDonald, of Gravelly Bottom Road, Maidstone, the two-hour polygraph test, which cost £595, found the youngster was 97% likely to be telling the truth.

He said: “Alexandra is really stressed. She has never been in any trouble before. This is the harshest punishment before expulsion.

“The report from the lie detector is 98% accurate, DNA evidence is 99%, so it does prove she is telling the truth.

“When I heard why she was excluded I had to get the school to repeat it twice, I couldn’t believe it.

“I asked for proof and was told it was on probability, a teacher saw them giggling in the same corridor but they didn’t see them with the nuts.

“The exclusion will be appealed to the school governors, so I got the lie detector done to prove her innocence. I told the school about the lie detector and they weren’t interested, it’s so frustrating.”

The school has defended its decision to discipline the two youngsters.

A spokesman said: “Following an internal investigation, we took the decision to temporarily exclude two students for their part in an extremely dangerous incident that could have had fatal consequences.

“We make no apologies and are surprised a parent of one of the students does not see the seriousness of their actions and is contesting the decision to exclude.”

It says parents and students are fully aware of its no-nuts policy, which has been in place for 20 years.

Alexandra says she was searching for her blazer, during a free period with friend 17-year-old Maddie Colley, when a teacher directed them downstairs to another classroom.

On returning they saw the crushed food on the floor but thought nothing of it as break time had just finished.

New Ash Green resident Maddie is preparing to sit mock exams in PE, geography and psychology.

Her mother Michelle Colley said: “It’s just really disappointing. It was Maddie’s 17th birthday on her first day of being excluded so that put a dampener on things.

“We’ve tried to convince the school but they’ve made their decision based on probability and they won’t listen to any other argument.

“I’m hoping they will reconsider on the new evidence. I don’t think we would go down the lie detector route but Maddie says she would take a test too.

“This will go on her permanent record if it doesn’t get sorted. I fully believe her, if it was a practical joke she would have admitted it by now.”

The school has defended its decision to discipline the two youngsters.

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