Arnold's flier lists a phone number: 555-123. Phone numbers in the United States must have at least 7 digits.
When Agatha is telling Arnold why she stopped writing, the paper in typewriter says, "Once upon a time there was a xx#w+rrvv!!" and "there" is spelled "ther."
Mr. Simmons said that the reports were supposed to be three pages, but Arnold's was just one page.
Arnold says the new book's title is The Weird-Headed Kid and the Mean Old Witch - but the book's actual title lists the witch first.
