I'm putting on my arm chair journalism cap to dig a little bit deeper into this before I get in to other things with my day.
I found two images in the journal that might be drawings of Colombine HS shooters. I focus on the second one because it's much easier to place. I made the connection most immediately because of the magazine in the gun. The other immediate connection is the rounded area of the hat the shooter wore. But I would like to point out some important distinctions/contrasts.