Troopers were called to the Avon Grove Charter School, located at 110 East State Road, West Grove, at about 11:18 a.m. on Wednesday, Oct. 9, state police said.
The knife is described as a pocketknife which was discovered when it fell out of the student's backpack, according to state police.
There was no threat to the school, the public, or anyone else involved in the case, state police said. There is no word on any charges. The investigation is ongoing.
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