I'm glad to know you're open-minded. Since you are, you'll be open to the fact that the reason most of these shootings happen at schools, theaters, malls, etc., is that they are gun-free zones. That fact offers no impediment to the individual bent on crime, but assures that there will be no one around to ventilate him when he opens up on innocent victims.
Not a single one of these mass murders could have been prevented by depriving law-abiding citizens of their right to own and use guns for hunting and self-defense. Criminals have always found a way to get guns, and gun-restrictive laws only keep citizens from defending themselves.
It is instructive to note that in Chicago, which has the toughest gun laws in the U.S., making it in effect the largest gun-free zone in the country, 444 children were killed by gunfire in 2011. Chicago also has one of the highest overall crime rates. But according to multiple studies by the FBI and others, violent crime rates have gone down everywhere concealed carry has been legitimized. Now that the courts have struck down Chicago's restrictive gun laws, expect the crime rate there to go down.
Although the media sensationalizes all such occurrences and the current administration has a policy of, in the words of Rahm Immanuel, "never letting a good crisis go to waste," mass murders have actually decreased since 2000. The peak year for mass murders, believe it or not, was 1929.
If anyone would like to do further reading on this issue, here is a blog post written by a a self-identified leftist, not a conservative.
http://kontradictions.wordpress.com...ew-the-assault-weapons-ban-well-ill-tell-you/