Erdenheim, Pa. ? An 11th-grader despondent that his parents might curtail his after-school activities because of poor grades took a rifle to school Tuesday and killed himself between classes at Springfield Township High School in Erdenheim, authorities said.

The gunman, Shane Joseph Halligan, 16, was an Eagle Scout and a volunteer firefighter whose poor grades had led his parents on Monday to threaten to cut back on his after-school activities, Castor said.

“The picture that’s emerging is he was despondent over (the fact) his grades are down, his parents are taking appropriate steps to limit extracurricular activities to get the grades up, and he saw the things that he felt were important in his life being taken from him,” Montgomery County District Attorney Bruce L. Castor Jr. said.