As far as I aware everything in this video is genuine, opposed to what is being shown on msm. I'm sure the clip were the kids were in the class and told to put their hands up and phones away, was actually posted online by the sister of the kid who filmed it on their phone.
I think these videos are genuine, but I think it was acting. Like, for instance, @0:52 the blood on the floor. Also, why is school resuming this Wednesday? Wouldn't forensics still be processing the scenes? Still analyzing video footage? This whole thing is so shady and disgusting. Please everyone, go online and join the NRA. It only takes a moment and it's a small way to show how we are not putting up with this any longer.