John Fund summarizes some useful facts on Multiple Victim Public Shootings

This is from John Fund's op-ed piece in the Hartford Courant:

•Mass shootings are no more common than they have been in past decades, despite the impression given by the media.
•In fact, the high point for mass killings in the U.S. was 1929, according to criminologist Grant Duwe of the Minnesota Department of Corrections.
•Incidents of mass murder in the U.S. declined from 42 in the 1990s to 26 in the first decade of this century.

•The chances of being killed in a mass shooting are about what they are for being struck by lightning.
•Until the Newtown horror, the three worst K–12 school shootings ever had taken place in either Britain or Germany.

From Vin Suprynowicz in the Law Vegas Review-Journal:

In 1974, three Arab terrorists broke into an Israeli school and killed 31 children and faculty. Did Israel respond by self-righteously asserting "Firearms have absolutely no place in our schools"?
No. Instead, they armed and trained their teachers and even parent chaperones, with the result that in the past 38 years, terror-beset Israel has not lost a single child within a school. . . . 

Here is a useful summary article from Fox News on guns in Israeli schools, though most might actually know what is written in the piece.

The Jewish state, which has long faced threats of terrorist strikes in crowded locations including schools, takes an all-of-the-above approach to safety in the classroom. Fences, metal detectors and armed private guards are part of a strategy overseen by the country’s national police. And the idea of armed teachers in the classroom, which stirred much controversy in the wake of the U.S. attack, has long been in practice in Israel, though a minority of them carry weapons today. 

Oren Shemtov, CEO of Israel’s Academy of Security and Investigation, noted that attacks typically happen in a matter of minutes, and said gun-toting teachers could, at the very least, buy time for kids to escape while police race to the scene. 

“Two (armed) teachers would have kept (the Newtown shooter) occupied for 45 seconds each,” said Shemtov, who is one of 16 people in Israel authorized to train those who instruct school guards. . . .  

Shemtov said the two most critical keys to protecting schools are armed guards and armed teacher response teams. But, as in the U.S., the idea of teachers carrying guns raised some objections in Israel, he said. 

“At one point the Interior Ministry mandated that a certain percentage of teachers be armed . . . ."