A Snowy Day - S1-E10
Revealing mistake: During the mailtime segment, when Mailbox shakes snow onto the chair, a small part of him is cut off, and you can see the letter being held behind him. This also happens when Mailbox opens his door, and you can even see a crew member's hand move away as Steve grabs the letter. (00:17:38)
A Snowy Day - S1-E10
Other mistake: When Mailbox comes in, he shakes some snow onto the chair. When Steve brushes it off, the snow stays visible on screen, then disappears mid-shot. (00:17:43)
