When I was 12, in the sixth grade in El Cerrito, California, one of my classmates brought a gun to school. She was a bright fellow student -- flamboyant, funny, sometimes moody -- occasionally in trouble, fun to play kickball with. I still remember her throaty laugh. I also remember the awful day while we stood on the play yard, as she pulled a gun out of her backpack and pointed it at a group of sixth-grade girls, threatening to shoot.