The National Teachers Hall of Fame has added a memorial to teachers who have died in the course of their teaching duties. While recent teachers such as the Sandy Hook victims and Christa McAuliffe come immediately to mind, the earliest teacher on the list (currently) is Enoch Brown, who died in 1764.
http://www.kansas.com/2013/06/08/2838384/national-teachers-hall-of-fame.html
The organizers are eager to hear about other teachers who are eligible for the memorial. Contact them at http://www.nthf.org/