• A middle school in Milton, Massachusetts, went into lockdown on Dec. 8 when a student reported that an adult "may have had a weapon," The Patriot Ledger reported.
After about 30 minutes of investigation by school officials and Milton police, however, it was determined that the "weapon" was a phone charger that a staff member was carrying.
"I am pleased to report that nobody was physically harmed," Superintendent James Jette said in a statement.
• On Dec. 3, a second-grader at Pamoja Preparatory Academy in St. Louis, Missouri, brought a loaded pistol to school to "show it to classmates," the Daily Beast reported.
The child said they took the gun from a lockbox under the parents' bed.
Two days earlier, at Woerner Elementary School in St. Louis, a kindergartner brought a gun to school when they picked up the wrong backpack.
Sgt. Charles Wall of the St. Louis Police Department said no charges will be filed in either case: "It was determined no criminal incident occurred," he said.