District spokeswoman Ebony Pugh says 44-year-old David Barkley collapsed Thursday morning at Pittsburgh Langley High School, where he taught machine operations. About 15 students were in the class at the time.
Pugh says Barkley was stricken about 10:30 a.m. and died about an hour later at Allegheny General Hospital.
Parents of students were notified and grief counselors were brought to the school Friday.
The Allegheny County Medical Examiner's office says an autopsy was not complete.
