One of the photographs that falls out of the music box is of Wednesday, Enid and Tyler in Tyler's car on their way to the Gates' home. There isn't enough time for the photo to be taken, developed and then placed in the home before they got there.
In the Eugene's hospital room, Wednesday is sitting with her backpack on the back of the chair. When Dr. Kinbott enters and Wednesday stands, the backpack is clearly still on the chair. A moment later Wednesday exits with the backpack suddenly on her back.
In Xavier's studio, Wednesday visits him to ask about the gate she has drawn. As the view pans around the room, the drawing of the monster's cave is clearly visible. Wednesday stole that drawing earlier; it should not be there anymore.
When Wednesday is in the Principal's office after discovering her room was ransacked, Principal Larissa (Gwendoline Christie) leans against the left side of the fireplace, but when the vantage point changes to looking out of the fireplace at her, she appears on the wrong side of the fireplace. When the vantage point returns to looking at her from Wednesday's perspective, she now appears leaning on the right-hand side of the fireplace without any indication that she moved.
(At around 33 minutes) Wednesday's lips do not match her voice for the line, "More seating for year-long Dia de los Muertos."
Wednesday's 16th birthday is celebrated. The previous episode established the time frame of this as being in November, 2022. The first episode established that Wednesday was born on Friday the 13th. In 2006, there were 2 Friday the 13ths, one in January, and one in October.
Enid calls her present to Wednesday a "snood". It is in fact a crocheted moebius cowl. A snood is a traditional piece of headwear for women, consisting of a band with a net or bag enclosing the full length of hair at their neck. The girls never wear these "snoods" in any manner but that of a scarf.
Upon being reminded that Mary Shelley wrote Frankenstein when she was 19, Wednesday, who is celebrating her 16th birthday, states that she has "2 years, 364 days" to beat her. That would only be true if Mary Shelley had written Frankenstein on her 19th birthday. Mary Shelley was born August 30, 1797, while Frankenstein was completed in April/May of 1816, meaning Wednesday would have until she was at least 19 years, 7 months old to "beat" Shelley.
When Wednesday's snood (a present from Enid) is returned to her, after she'd left it at the coffee shop, she remarks that it has returned to her "like a monkey's paw." The story of the monkey's paw is that it is a cursed object that grants wishes but in a way that twists the wisher's intent based on the language used. There's nothing in it about unwanted items, including the paw itself, returning to someone.
When Wednesday tells Tyler to "drive" away from Nevermore, neither she nor Enid is wearing a seat-belt.