The 15-year-old and others were caught smoking in a William Allen High School bathroom when the school resource officer searched their belongings and came across the weapon, APD said.
The youth was charged with carrying a firearm without a license, a felony, and related misdemeanor counts, the department said.
He is also charged with marijuana possession.
"We communicated information with staff and families regarding a safety incident and the recovery of a weapon," a school district spokesperson told Daily Voice.
"We continue to strengthen safety measures and yesterday, met with Mayor (Matthew) Tuerk and (APD) Chief (Charles) Roca to review and outline future collaborative action steps."
"We have planned a community forum and a survey is being sent to families today to enlist their feedback on overall safety and consideration for installing metal detectors," the spokesperson said.
"The District is committed to ensuring a safe learning environment for every member of our learning community."
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