So Long and Goodnight

I've had a chat with every one of the kids about their sudden injuries, and of course, they haven't said a peep, which makes me wonder just how much this principal is doing... But I have a plan. I'm gonna follow one of the them the next time they talk, and see what happens. I already know what's going on, and like any teacher I'm gonna stop it, but I need evidence.
And as I expected, Zepplin was caught on his phone, so Miss W escorted him outside, and sent him to Mr. Holmon's. A bit later, I ask Miss W if she can watch over the class, while I go get a mug of coffee from the teacher's lounge. She happily agrees and takes my seat as I exit.
I see the kid still walking over there, a lot less confident than he was when he was walking out, even shaking, rubbing his arms. He touched something late looked like a tiny Bluetooth headset and sighs, turning the corner. I turn the same corner and jump slightly when I see him leaning on the wall, looking straight up at me, when I make the turn. "Why are you following me?" he asks.
"I'm...I'm not following you." I say. But I lie badly, and he quirks an eyebrow. "I was heading to the teacher's lounge."
"The teacher's lounge is that way." he says, pointing the opposite direction. I nod and turn around, beginning to walk the opposite direction, until he turns back around and continues walking. I'm get a little angry, well, more like envious that he could tell me off. Teacher instinct? "Smartass." I mutter like a kid that lost a board game, once he was a few yards away.
"Heard that." he shouted, not even looking back. "And recorded it." he said, tapping the mini-headset. as he walks through the door to Mr. H's office.
Once the door's shut, I run as quietly as I can, and look through the window, seeing the abuse. I want to shut my eyes but I can't, I just stand there, watching the whole thing. I can't even say what I saw, it's too...disturbing, I just walk back to my room, with shocked eyes, and open the door, walking back in and taking my seat.
"Where's your coffee?" askes Miss W, making me shoot up to look at her. "My what?"
"You said you we're going to get coffee..."
"I drank it."
She nods, and we both wait there until the end of the day and the kids hand their projects in on my desk, but Zepplin walks to my desk after everyone else's left.
He says his words without hesitation. "I know you saw it."

Notes

...Yeah, happy reading...