A pellet gun was discovered in the backpack of a student at Jupiter High School Wednesday morning, according to a robocall to parents from the principal.
She said school police began an investigation after administrators were tipped off.
School police found the pellet gun after 'isolating' the student in question, the call to parents said.
That student, who was not identified, was arrested.
The school reminds students who 'see something to say something.'