
School Play - S3-E19
Other mistake: After Helga gets mad at Arnold in the beginning, as Helga says, "What an annoying little smarty pants know-it-all," the lunch lady's body is invisible through the glass on the counter, leaving only her upper half visible. (00:01:12)

Full Moon / Student Teacher - S4-E1
Other mistake: Full Moon: When Arnold tells Sid, Stinky, and Harold that he was given four weeks' detention, Harold tells him to not rat on them. Arnold says he won't tell, and when he walks away, his hair passes right through Sid's head. (00:03:30)

Big Gino / Jamie O. In Love - S4-E2
Other mistake: In the cafe, after Charice speaks, when Gerald says "Aloha, Gladiators on Ice", there are three places where Gerald's mouth disappears.

Dinner for Four / Phoebe Skips - S4-E5
Other mistake: Dinner for Four: When Arnold and Lila are talking to each other in the beginning, Lila says that she hopes to become a famous ballerina one day if she practices hard enough. In this shot, a stripe on her shirt is mistakenly drawn over her gold button. (00:01:26)

Dinner for Four / Phoebe Skips - S4-E5
Other mistake: Phoebe Skips: When Lila tells Helga, "I just didn't feel right about destroying Rhonda's personal property," she blinks, and her right eyelid is not colored in. (00:16:19)
Dinner for Four / Phoebe Skips - S4-E5
Other mistake: When Helga and Phoebe leave the girls' bathroom together near the end, Helga pushes the door outward, but the hinges are on the inside, so it should only open inward.

Love and Cheese / Weighing Harold - S4-E7
Other mistake: Love and Cheese: When Arnold accidentally kisses Gerald's hand on the bus, his left foot is missing. (00:02:00)
Love and Cheese / Weighing Harold - S4-E7
Other mistake: Love and Cheese: When Arnold and Lila's boat is stuck at the edge of the waterfall, as Lila says, "Arnold, what will we do?" a piece of the boat next to Lila is incorrectly coloured like the background and the seat, so it looks like a hole in the boat. (00:10:14)
Love and Cheese / Weighing Harold - S4-E7
Other mistake: Love and Cheese: When Arnold and Lila grab each other's arms on the boat, part of Arnold's left arm becomes invisible. (00:10:18)
Love and Cheese / Weighing Harold - S4-E7
Other mistake: Love and Cheese: At the end, when Arnold says to Lila that he will walk her home, they both start walking to the right, then Lila vanishes while on screen. She never leaves the frame. (00:11:42)

Back to School / Egg Story - S4-E8
Other mistake: Back to School: After Principal Wartz tells Phil he will find a classroom for him, it cuts to a shot inside Mr. Simmons' classroom. If you look at Sid in this shot, the lower half of his body is cut off. Phoebe's right foot is also layered over him. (00:03:58)

Back to School / Egg Story - S4-E8
Other mistake: Back to School: After Phil completes his long division on the chalkboard and it cuts to a shot of Arnold, the shot is flipped, with Arnold's hair being the most notable giveaway. (00:04:43)

Back to School / Egg Story - S4-E8
Other mistake: Egg Story: When Arnold tells Helga, "I know you don't like me, and frankly, you're not my favorite person either," his mouth disappears twice. (00:14:51)

Weird Cousin / Baby Oskar - S4-E11
Other mistake: Stephen Viksten is credited twice for voicing Oskar.
Grandpa's Sister / Synchronized Swimming - S4-E12
Other mistake: Synchronized Swimming: When the boys take off their jackets during the swimming tournament, Arnold's jacket is floating in mid-air, and the left side of Eugene's jacket is also in mid-air. (00:20:45)
Grandpa's Sister / Synchronized Swimming - S4-E12
Other mistake: Synchronized Swimming: Right before the boys jump into the pool during the swimming tournament, Gerald's right eye seems to have lost its color. Right when Sid jumps into the pool, his eye is white again. (00:20:52)

Grandpa's Sister / Synchronized Swimming - S4-E12
Other mistake: Synchronized Swimming: During the swimming tournament, when the boys jump in the pool and it cuts to the crowd, Lila's dress and bows are incorrectly coloured blue, and they stay that colour for the rest of the episode. (00:21:04)
Monkeyman! / Buses, Bikes and Subways - S5-E1
Other mistake: Buses, Bikes, and Subways: When Helga and Harold are running to catch the bus, as Harold says, "Ow, quit pulling my arm," Helga is frozen at the right side of the screen for a second before she starts moving. (00:14:49 - 00:14:53)

Monkeyman! / Buses, Bikes and Subways - S5-E1
Other mistake: Buses, Bikes, and Subways: When Helga and Harold enter WrestleMania, as Harold says, "He lets me in all the time," the legs of the people sitting in the front row are cut off. Their chairs don't have any legs either. (00:22:03)

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.






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 ★