Ralphie imagining his teacher Miss Shields as the Wicked Witch
I never fully realized how genuinely creepy this little part is until recently:
https://www.youtube.com/watch?v=kvrDKlV2Kw0
Maybe because it feels so random and Miss Shields is otherwise very stoic and serious acting instead of being a cackling mad woman. And then you have Ralphie's mom dressed up like a court jester laughing along with Miss Shields over Ralphie's misery.