I first heard about the bulletproof backpacks on CNN. Then I found that it was apparently true when this story from the Boston Herald popped up in response to my search for more information:

Dads Mike Pelonzi, 43, and Joe Curran, 42, dreamed up the bullet-proof backpack, which also blunts knife attacks, to protect their own children after witnessing the Columbine massacre in 1999.
?It was after seeing what happened in Columbine that we started thinking about this. I?m a parent and so is Joe and we wanted a way of keeping kids safe at school and this is what we came up with,? said Pelonzi, co-owner of MJ Safety Solutions which produces ?My Child?s Pack?.
The backpacks, which will cost $175, have a super-lightweight bullet-proof plate sewn into the back which weighs no more than a bottle of water. Pelonzi said the material used is a secret.
The plate material meets National Institute of Justice safety standards, said Pelonzi, and during a three-year testing phase, stood up to bullets as well as machete, hatchet and Ka-bar knife attacks. (Dads push bulletproof backpacks in schools, Mike Underwood, August 9, 2007, Boston Herald)

Boston school officials still have to decide whether or not their students can use the bag, since the dress code prohibits a student from wearing “anything which is threatening or offensive.?
I am firmly convinced that there is a better response to school violence, and we should be thinking of how we can make our schools more nurturing places. Anybody who is not with me on this might be interested in My First Riot Gear.