Robert's hair changes color from blonde to black and back several times throughout the episode.
Robert also vanishes during the Carm Helga scene.
At Arnold and Curly's fight scene, when Curly runs away, he steps on Rhonda's head like it was part of the background.
Ruth is seen on the field trip with the rest of Arnold's fourth grade class despite being a sixth grader.
She is however briefly seen talking to Maria and Connie (also sixth graders) at one point. This may imply that the field trip was for multiple grades (which could also explain why Mr. Packenham is taking the 4th graders despite being a 5th grade teacher).
Wolfgang Amadeus Mozart is credited among the composers in the opening credits, most likely an erroneous credit to Gerald's "Figaro, Figaro", often misattributed to his opera The Marriage of Figaro. It is actually from the aria Largo al factotum from Gioachino Rossini's The Barber of Seville.
