The student, who police didn't identify because of their age, was charged with two counts of second-degree uttering threats and breach of peace.
Police were called to the school at 10:44 a.m. Monday after the email was received, police Sgt. Sofia Gulino said.
The email had a link to a social media post and and also to a video, she said. She declined to say what the posts referred to.
"At no time was there a plausible threat to the school, and the investigation showed that the student had no means to carry out the threat," Gulino said.
A search was conducted of the school and of the student's home, Gulino said with the cooperation of the school and the student's parents.
Police are withholding the juvenile student's name, age and gender.
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