Monkeyman! / Buses, Bikes and Subways - S5-E1
Revealing mistake: Monkeyman!: When Arnold tells the kids that Monkeyman saved him, as he says, "He went after the two guys who were trying to mug me," he moves his right hand, and it's layered over Helga's hair. (00:01:25)
Monkeyman! / Buses, Bikes and Subways - S5-E1
Continuity mistake: Monkeyman!: When Sid tells the kids that Gerald should tell the legend of Monkeyman, Arnold is squinting. In the next shot, he's not. (00:01:41)
Monkeyman! / Buses, Bikes and Subways - S5-E1
Audio problem: Monkeyman!: When Gerald begins to tell the legend of Monkeyman, as he says the word, "Monkeyman," it looks as if his mouth only says the word, "Man," and it never says the "N" sound at the end. (00:01:50)
Monkeyman! / Buses, Bikes and Subways - S5-E1
Audio problem: Monkeyman!: When Gerald finishes telling the legend of Monkeyman, Stinky can be heard saying, "That was beautiful, Gerald," but his mouth doesn't move. (00:02:32)
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
Audio problem: Buses, Bikes, and Subways: When Helga and Harold are running to catch the bus, as Helga says, "The bus is leaving, you dumb oaf," her mouth does not move. (00:14:49)
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
Revealing mistake: Buses, Bikes, and Subways: When Helga and Harold are riding the clown bike, a tall clown and two little clowns start chasing them. As the clowns are running, the left little clown is layered over the tall clown's right leg for a few frames, and the right little clown runs right through it. (00:17:39)
Monkeyman! / Buses, Bikes and Subways - S5-E1
Continuity mistake: Buses, Bikes, and Subways: Helga wears a watch on her right arm throughout the episode. However, when Helga approaches Sheena's uncle Earl and wakes him up, her watch is missing, then reappears when Earl's boat sinks. It disappears again when Helga comes up from the water, then reappears a moment later. (00:18:59)
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)
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)
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).
Answer: The show is based in present day times. Plus most cars aren't old fashtioned, I recall seeing a limo and not to mention a cherry picker, etc.