The Delaware County Daily Times reports 19-year-old Upper Darby resident Darlington James entered Upper Darby High School on Feb. 19 and knocked on a classroom door. Investigators say the teacher opened it and James beat her with a hammer before stealing a computer. He was arrested nearby.
Investigators say James, who isn't a student, was involved in a similar incident at the middle school in January. His arrest also led to a third robbery charge being filed after police say he attacked and robbed a 16-year-old student in a park.
James pleaded guilty Friday to three counts of robbery and one count of aggravated assault.
Information from: Delaware County Daily Times, http://www.delcotimes.com