Magic Show / 24 Hours to Live - S1-E18
Continuity mistake: The boarding house has a downstairs bathroom, but in "Gerald Comes Over", there's only one bathroom and it's upstairs.
The Little Pink Book/Field Trip - S1-E2
Continuity mistake: Arnold is talking to his Grandma about the turtle. There is a table in front of them with three items on it: a remote, a magazine, and what looks like food with a cup. In one shot, the items move around at least twice, depending on which angle the shot is.
The Little Pink Book/Field Trip - S1-E2
Continuity mistake: The orange juice container on the table jumps around when Arnold's grandpa is talking to him about his crush. First it's in the middle of the table, then it moves right. Then back and right again.
The Little Pink Book/Field Trip - S1-E2
Continuity mistake: Arnold puts the pink book on top of a bookshelf at an angle. When Helga comes into his room moments later, the book is upright.
Save The Tree / New Teacher - S2-E1
Continuity mistake: New Teacher: At the start, Principal Wartz writes Mr. Simmons' name on the chalkboard. Then, when Mr. Simmons walks over to the desk, the writing is missing from the chalkboard; it reappears a moment later. (00:12:07)
Continuity mistake: When Rhonda asks Lila if she wants to take the marriage predictor test, Lila is holding three books, but she is only holding one book in the next shot. (00:01:42)
Monkeyman! / Buses, Bikes and Subways - S5-E1
Continuity mistake: Buses, Bikes, and Subways: When Mr. Simmons shows the class the huge vat of chocolate, Phoebe points out that somebody is swimming in it. Then in the shot where Chocolate Boy rises up out of the chocolate, behind the vat, there is another vat which wasn't there before. (00:13:48)
Monkeyman! / Buses, Bikes and Subways - S5-E1
Continuity mistake: Buses, Bikes, and Subways: After Helga and Harold first encounter Earl, it cuts back to the class on the bus. Phoebe is not sitting in the seat behind Arnold and Gerald, but in the next shot, she suddenly appears. (00:19:10)
Helga's Boyfriend / Crush on Teacher - S2-E14
Continuity mistake: Helga's Boyfriend: At the Stake Time roller rink, when Helga and Stinky are spinning around like a tornado, all the kids are standing around them, but they all disappear in the next shot. (00:03:58)
Helga's Boyfriend / Crush on Teacher - S2-E14
Continuity mistake: Helga's Boyfriend: At the Skate Time roller rink, when Helga and Stinky first start spinning around, there is a close-up of Ruth, and her skirt is its usual red colour. In the next shot, it changes to blue, the wrong colour. (00:03:55)
Helga's Boyfriend / Crush on Teacher - S2-E14
Continuity mistake: Helga's Boyfriend: At the library, when Helga tells Stinky to help her into her chair, there is a white folder and a yellow pencil on the table. Two shots later, they change to a red folder and a pink pencil. Two more shots later, the folder changes to green. (00:02:56)
Helga's Boyfriend / Crush on Teacher - S2-E14
Continuity mistake: Helga's Boyfriend: When Helga asks Stinky to be her boyfriend, as Stinky says, "Well, could you make it a Mr. Nutty candy bar?", the trays, fork, and Helga's hands are on the table. In the next shot, everything disappears from the table, then Helga's tray and fork reappear in the following shot. (00:02:16)
Arnold Betrays Iggy / Helga and the Nanny - S3-E10
Continuity mistake: Helga and the Nanny: After Helga tells the kids that she took her father's belt instead of Inge, Arnold tells her that he can't believe she would do something that mean, then he gets up and leaves. He is not holding his lunchbox in this shot, but his lunchbox appears in his right hand a shot later. (00:20:12)
Arnold Betrays Iggy / Helga and the Nanny - S3-E10
Continuity mistake: Helga and the Nanny: In the shot after Helga tells the kids that her father fired Inge, Arnold's lunchbox has a baseball and baseball bat symbol on it, but two shots later, the symbol is gone. (00:19:52)
Arnold Betrays Iggy / Helga and the Nanny - S3-E10
Continuity mistake: Helga and the Nanny: Near the start, in the shot where Miriam leaves to go to work, there is an orange vase with flowers on the table, which was not there in the previous shots. (00:11:53 - 00:13:09)
Freeze Frame / Phoebe Cheats - S2-E8
Continuity mistake: Phoebe Cheats: In Phoebe's room, there is a green mat on her desk, but it is missing in all the wide shots from behind Phoebe as she sits at her desk. (00:12:50)
Freeze Frame / Phoebe Cheats - S2-E8
Continuity mistake: Phoebe Cheats: After Phoebe reads the poem from her book, it then cuts to a wide shot from behind her; only she is not holding the book anymore; she is writing on her paper with her pencil. In the next shot, she is holding the book again. (00:14:00)
Freeze Frame / Phoebe Cheats - S2-E8
Continuity mistake: Phoebe Cheats: After Phoebe reads the poem from her book, she sets the book back against the lamp, and there is a blue book under the poem book. In the next shot, the blue book disappears. The location of the lamp and poem book also changes. (00:14:05)
Freeze Frame / Phoebe Cheats - S2-E8
Continuity mistake: Phoebe Cheats: When we first see Phoebe writing her poem in her room, the red book beside her repeatedly changes direction depending on the shot. (00:12:49)
Continuity mistake: When Pea Pod Kid is taking Rhonda's marriage predictor test, Sid is walking down the stairs behind them. In the next shot, he disappears. (00:03:44)






Answer: The episode doesn't really elaborate on who the kid was and what his motives were, so its pure speculation as to why he took it. Perhaps the kid could simply want a ball all for himself and decided to just take it, or was simply a rotten kid. The truth is the kid's motives are not important to the story other than it highlights Arnold was having a lot of trouble getting through the list.
Lummie ★