Certain shootings should be discussed with kids, especially school shootings. Kids are not completely cut off from the news and would probably hear about shootings anyway, so it is best to sit down and discuss it with them so they understand what is going on. Kids have a right to know and understand these tragic events.
I have a very open policy with my kids. I made sure to sit them down and talk to them about the Sandy Hook massacre, to let them know what had happened and to answer their questions. They are already hearing misinformation from kids at school, and if I hadn't taken the time to talk with them, they would be terrified and confused.
Children deserve to understand what is happening in the world, and they need to be guided through this understanding by those who love them. It is important to discuss things like shootings with kids, since they will be hearing about them from their friends and teachers. Nothing should be kept from children if those children are curious about the subject. By doing so, you just lend an air of importance and mystery to that subject which makes kids all the more curious. When a child asks about a subject, no matter how difficult that subject may be to discuss, it's the duty of adults who love that child to help the child understand. If the adults don't understand themselves, it is perfectly OK to admit that to kids, too.
To discuss shootings with our kids is an admission that we as parents are out of control, that there is a bigger world out there that is dangerous and we can't do anything about it. A kid doesn't need to know about a shooting unless it happened right in front of them. This latest shooting of young children led to a media orgy about how we should handle it with our own kids. We shouldn't have to, it's only the media saturation that allows our children to obtain knowledge of these things. The parents in Newtown have to discuss it because their kids were subjected to it, but the idea that every parent needs to have a sit down talk with their own children is a result of our own obsession with the subject. There are things that parents should be able to accomplish without dragging their kids emotionally into something they do not need to address. Instead, turn off the media, go to a community meeting of adults and decide how to fix this so we don't "have to" talk to our kids about it. To do anything else is to admit to our own kids that we are helpless in the face of so much evil in the world.