A Swedish girl who refused to join her classmates in skipping school for the sake of the climate has ended up being labelled as a "climate denier", which her mother described as "mass psychosis".

A high-school pupil who refused to attend a so-called "school strike for climate" has been bullied not only by her classmates, but the teacher as well, the magazine Det Goda Samhället reported.

When the girl's classmates decided to join the "climate strike" spearheaded by teenage activist-turned-superstar Greta Thunberg, "Sanna" declared she didn't want to attend and was given a tongue-lashing from the teacher.

"The teacher said 'Sanna' was uncommitted and failed to understand the seriousness of the climate threat. She asked her to reconsider her decision, and she said it openly, for the entire class to hear. 'Sanna' felt like the teacher was trying to ridicule her in front of the others", "Lena", the girl's mother, told Det Goda Samhället.

Because of the teacher's actions, the rest of the class also turned against "Sanna", who ended up being boycotted by her own friends and accused of being a "climate denier", "Lena" recalled.

When the mother called the school's administration, she herself was questioned by the female principal.

"She said it was sad that 'Sanna' went against the rest of the class and refused to participate in something this positive. I could read between the lines that she thought I had a wrong attitude myself", "Lena" explained.

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The mother called the situation a "mass psychosis" and said it was "very unpleasant".

"If you are not a fan of Greta Thunberg and her 'school strikes' for the sake of climate, then you should be boycotted and bullied. This is totally sick", the mother explained.

According to her, "Sanna" now refuses to go to school, she is worried and afraid of what may happen.

Greta Thunberg is a Swedish climate activist who rose to international fame for her weekly "school strikes" held outside of the Swedish parliament. As her movement rose to prominence, hundreds of thousands of students in over a hundred countries across the globe have followed her example.

For her relentless activism and penchant for doomsday rhetoric, Thunberg received a lot of traction, having met with EU officials, top-ranking businessmen and even the Pope, and was decorated with a lot of prizes and awards. In March 2019, she was nominated for the Nobel Peace Prize by Norwegian MPs. In May 2019, at the age of 16, she starred on the cover of the Time magazine. In her home country, she was appointed the woman of the year by two of the country's largest newspapers, Expressen and Aftonbladet.

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In Scandinavia, she is known as "Climate Greta" and receives a lot of media coverage and is almost universally venerated by the political establishment despite her repeated criticism of their actions as insufficient. Sweden's goal to become carbon neutral by 2045 has been called "the world's most ambitious climate law".

​However, her name also sparks a lot of controversy. First, many are sceptical of Thunberg's stance due to her diagnoses of Asperger's, obsessive-compulsive disorder (OCD), and selective mutism. Second, her name is often misused. In late 2018, Ingmar Rentzhog, founder of the non-profit We Don't Have Time Foundation, who claims to have "found" and "developed" Thunberg, recruited her to become an unpaid youth advisor and used Thunberg's name and image without her knowledge or permission to raise millions.