Hmm...

This is actually pretty interesting to me. I've done a number of research projects for school on Columbine, and when I've seen about the levels created it was framed as "these were made as a model of the school to 'practice' for the actual event", so this is news to me. It'd be next to impossible to find out if it does exist, let alone recovering it, though. I mean, for all we know, the kids who were told about it could have just misunderstood what it was.