The entire group erupting into panic once Delilah reveals herself as an infected, with all the guys trying to will themselves into shooting her. And then Stokely bursts through the crowd and goes "I'll fuckin' shoot her!" and fires about five bullets in Delilah's general direction.
While it's Mood Whiplash, when the coach stabs the principal with a pencil he says, "I've always wanted to do that." The principal thinks she's made it to safety, locking him inside, another teacher stabs her repeatedly with a pair of scissors, and then says, "I've always wanted to do that."
Casey and Delilah find Mrs Bromwell's body (?) in the closet and come back with the police. The body has been moved and replaced with a mannequin used for life-saving practice. The principal remarks that the doll does have a strong resemblance to Mrs Bromwell.
They kidnap the Alien!Principal and tie her up in a net. Her response? "You're all expelled"
Zeke is trying to keep serious during the whole getting high scene. But Delilah's bitchiness makes him burst out laughing at random.
Zeke: (laughing) Is she always this much fun, man?