Ron is pleased that his new look attracts high school girls who are seniors, anticipating the battle against another kind of Seniors.
The location Kim states for the Seniors' uncharted island doesn't have an island in real life. It's about midway in the mouth of the Bay of Biscay in the Atlantic Ocean, about 160 miles north of Punta de Estaca de Bares, Spain and 220 miles southwest of Point du Raz, France.
First appearance of Señor Senior Senior and Señor Senior Junior.
Ricardo Maltoban, the voice of Senior Senior, played Kahn in the original Star Trek series and the movie Wrath of Kahn. George Takai, who played Sulu in the original Star Trek and the six Star Trek movies, voices Sensai in later episodes.
The Seniors' map indicates that Middleton is in Colorado. There is in fact an unincorporated community with such a name in San Juan County in that state, but it does not resemble Kim Possible's Middleton. This is one of several purposefully contradictory clues through the series regarding the location of Kim's hometown. See trivia for the series.