. doug estle is the principal at murphy high school.he has a great rapport with his students. but one afternoon on may 18th,  2007, one of those students commits a violent and senseless crime. >> a student was being placed under a suspension from a  teacher's classroom. >> 16-year-old randolph parker, seen here in the blue shirt,  khaki colored pants, is the  problem student in 61-year-old melissa's ninth grade english class. she's giving a party that  afternoon in her classroom for an exchange student who's  returning home. although randolph parker had been suspended earlier that day he returns later and paces outside her door. >> obviously through his anger, he wanted to take out revenge, blamed her for the problems he had been having. so he set up a plan, obviously, to come back at the end of the day to attack her or to hit her >> as this last period  progresses, you can see randolp parker, w