Officials in the Derry School District in Dauphin County, Pa., gave the boy -- identified in the federal lawsuit as G.B. -- a four-day suspension and branded him a "weapons offender" for possessing the pen, which emits a small electrical shock when the cap is pressed, the Philadelphia Daily News reported Thursday.
G.B. is a second-grader at Hershey Elementary School in Hershey, Pa., the newspaper added.
"A sharpened pencil is probably a more dangerous item than this pen was," said the boy's attorney Aaron Martin, who noted the goal of the suit is to clear the boy's name and to clarify what can be brought to school.
The suit, filed in U.S. District Court in Harrisburg, Pa., claims the boy is classified as a violator of the school's weapons policy, his disciplinary record is permanently "marred," and he is "relegated to the same category as violent criminals" and terrorists.