Court documents reported by WTSP-TV say a teacher at Avon Park Middle School spotted the 14-year-olds acting "hysterically" Wednesday while seeking a folder and overheard them say they would be arrested if anyone found it. She heard one say to tell police it was a prank.
The teacher found the folder and saw a mention of guns. She alerted school officials and its police officer.
Officials say the folder included plans for getting guns, killing the victims, and disposing of their bodies.
They are charged with conspiring to commit homicide and commit kidnapping.
Prosecutors in the central Florida county didn't say whether they will be tried as adults. They are now in a juvenile jail.
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