
Continuity mistake: At the start, Lila is sitting on a bench near the school wall. However, in the shot where Sheena says, "Oh, that's wonderful," Lila and the bench are missing; then they reappear a moment later. (00:01:13)

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)

Timberly Loves Arnold / Eugene, Eugene! - S5-E22
Other mistake: Eugene, Eugene!: The hat Lila wears with her Betty costume has a yellow crown with a green ribbon around it. However, when Arnold sings, "Nice Guys Finish Last," as he sings, "Take his money, grab his honey," the crown of her hat is entirely green. (00:17:00)
Timberly Loves Arnold / Eugene, Eugene! - S5-E22
Other mistake: Eugene, Eugene!: When the kids sing "Sunny Side Up" at the end, as they sing, "Who cares if the day is foggy and gray?", the crown of Lila's hat disappears for one frame. (00:22:46)

Grandpa's Packard / Phoebe's Little Problem - S5-E19
Other mistake: Phoebe's Little Problem: When Arnold goes into Phoebe's room to cheer her up, the birdcage is reflected in the mirror on the wall, but the birdcage is too far to the right of the mirror, so it shouldn't be reflected. This error is shown again in a later shot where Phoebe tells Arnold, "And I'm very good at checkers." (00:09:13 - 00:09:45)
Helga's Locket / Sid and Germs - S5-E7
Plot hole: Helga's Locket: When Grandpa tells Arnold about his grandfather's Shiska-Bob Stick, he says that no one has ever touched it since his grandfather's last barbecue on July 16, 1926. However, in the season 3 episode "Grandpa's Birthday," Grandpa says that his grandfather died in 1921 while he looks at the photo album. (00:09:55)

Continuity mistake: Phoebe is going into the school in one scene, but as the camera moves she vanishes while on screen.

Parents Day - S5-E6
Continuity mistake: In the scene where Arnold's parents leave for the last time, Grandma's hair is dark at first, then it becomes purplish-gray.

Sid the Vampire Slayer / Big Sis - S5-E3
Other mistake: Sid the Vampire Slayer: While Sid stands in front of the mirror and points his rubber sword at Arnold and Stinky, the two ghoulish vampires, Arnold asks him, "How can we be vampires if we have reflections?" So when Sid is aware of his mistake, Arnold's eyes disappear and reappear in his reflection mid-shot.

Parents Day - S5-E6
Continuity mistake: During the flashback, when little Arnold says goodbye to his parents, in the next shot of Stella and Miles, the bag's strap is slung over his dad's left shoulder as a crossbody, but mid-shot, the strap switches to his right shoulder with the bag on the opposite side. (00:14:30)

Parents Day - S5-E6
Continuity mistake: When Grandpa enters and exits Arnold's bedroom, the door opens the opposite way in various shots, with the doorknob on either the left or right. Additionally, the light switch beside the door appears and disappears, between shots.

Helga's Masquerade / Mr. Green Runs - S5-E2
Other mistake: Mr. Green Runs: When Green tells Arnold he can't be himself and needs to come up with some fancy words, Arnold is wearing a "Vote Green" button. Then, just as Green says, "I gotta get outta here," Arnold's button now reads "Voet Green" with Vote misspelled.
Character mistake: The first time Arnold tries Rhonda's marriage predictor test, he says his favorite number is five, but Rhonda actually makes six moves. The second time, Arnold says it's three, but Rhonda counts off four.
Monkeyman! / Buses, Bikes and Subways - S5-E1
Continuity mistake: Mr. Simmons counts 30 students in the bus, but nowhere near that many got off (nor have nearly that many fourth graders ever been shown).
Ghost Bride/Gearold VS Jameo - S5-E25
Continuity mistake: In the scene where they are running from the second ghost bride, they go into a crypt and close the doors. One of the kids puts a shovel through the handles to keep it shut. In the next shot, it's gone. In the shot after that it's back.

Beaned / Old Iron Man - S5-E11
Continuity mistake: When Arnold reads to Helga, the book title says "GEO-" and "GRAPHY" (two words); the next day, it says "GEOGRAPHY" (one word).
Stuck in a Tree / Rhonda Goes Broke - S5-E10
Other mistake: In the scene after the garbage dumpster scene, Buckley's lips disappear briefly while he's talking.

Helga's Locket / Sid and Germs - S5-E7
Other mistake: Helga's Locket: When Helga climbs to the top of the boarding house and looks at Arnold and Grandpa through the window, as Arnold tells Grandpa, "It's embarrassing and weird," Helga's left sleeve is incorrectly coloured pink instead of white. (00:09:02)
Helga's Locket / Sid and Germs - S5-E7
Continuity mistake: Helga's Locket: When Abner takes the locket from Helga at the end, Helga chases after him. In the next shot, they are shown running past the basement window of the boarding house, but that's impossible because they started running away from the basement window in the previous shot. (00:11:42)
Helga's Locket / Sid and Germs - S5-E7
Audio problem: Helga's Locket: When Abner takes the locket from Helga at the end, Helga screams, "Come back here, you filthy pig!" but her mouth hardly moves. (00:11:42)
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 ★