Continuity: Besides the fact that when Helga is sharpening her pencil, the desk arrangement changes, one of the students visible when she looks at Arnold is...Helga.

Audio problem: Right after Helga is standing behind the "ARNOLD" on the pavement, when she says "Hey Arnold", her lips move as if she's saying it slowly (this is fixed in the 4th season).

Continuity: When the four boys form their line (just before the adults call out "Arnold"), watch Harold's tooth; it goes from the right side of his mouth (as you look at him) to his left side.

Continuity: On the "Presidents of the United States" sign behind Helga, the word "United" becomes "Nvited"

Audio problem: At the hat store, when Arnold says "Huh? What are you, nuts?", his lips don't move - but Gerald's do.

Continuity: In "Longest Monday" at one point in the episode, Arnold and Gerald run off of a bus and down an alley. Two fifth graders come chasing after them. In the next scene, you see Arnold and Gerald hiding in the sewer under the 5th graders. Arnold then crawls through a very narrow tube, and Gerald follows. You then see the end of the tube and Gerald come out of the it first, and Arnold climbs out last. It would be impossible for Arnold and Gerald to switch places inside the tube because it was way too narrow.

Audio problem: When Arnold is playing chess with the Sewer King, Arnold jumps across the table and knocks the King over. This sequence appears to be sped up: the toilet crashes way after it is destroyed, and the King says "Noooooooooooo," yet his mouth never moves.