I am largely in agreement, though I would add two things.
A more refined definition of hero: to be a hero, one must take action to aid another that is at least in someway effective at great risk to one’s self. This lady qualifies.
I also doubt that teachers have always been defanged. There is a great chapter in Farmer Boy (one of the books in Laura Ingals Wilder’s Little House series) relating an incident in a one-room school house in upstate New York in the mid-19th century. The bigger boys in the class had beaten the previous teacher so that he had to leave and eventually died as a result of the beating. A friend of his took the position and practiced privately with a bull-whip, which he kept in his desk and used when the day for its use came. From what I have read of 19th century schooling I am sure that this was not unique.
I like your two things.