When the group of Nevermore students confront Tyler in the beginning, Divina's eyes are dark. In all other scenes she appears in, her eyes have the trademark sea-foam coloring of a siren.
Near the end, in Weems' office, a crew member can be seen reflected in the mirror at the far end of the room on the left-hand side of the screen.
The moon is full, yet Enid is the only werewolf who transforms, even though the student body at Nevermore is said to be about a quarter werewolves. She also changes back into her human form while the moon is still out.
After the meeting in the Nightshade library, Enid is surprised when the Nightshades (including Thing) all perform the "secret snap." She would have heard Ajax perform the snap when they entered the library.
Wednesday accidentally says "Tyler warned me that something bad was coming" when it wasn't Tyler. It was Rowan. (39:42)
Wednesday repeatedly mentions Tyler kissing her but she was the one who kissed him.