Mayan Palace Theatre San Antonio Texas a gunman was shot by an off duty policeman working at the theatre Sunday night published Monday Dec 17, 2012
Jesus Manuel Garcia 19 year old shot one bystander charged with aggrivated assault
Watch the youtube video  video unavailable
San Antonio shooting gets no national attention
Armed Defenders DO Stop Mass Murders   Another account of the same shooting in San Antonio

School resource officer kills gunman at Sullivan Central, a school in Tennessee link expired

Man defends himself against teenage robbers with tent pole, gets demoted
Delivery Driver Demoted After Fighting Back link expired

Pearl High School shooting of 1997  school assistant principal with .45 stops shooter
Wikipedia article on the shooting
another link