Love and Cheese / Weighing Harold - S4-E7
Trivia: In 'Weighing Harold', when Arnold is in the comics store, there are comics in the background referencing other Nickelodeon shows, "Catdog" and "Spongebob Squarepants." The former had aired almost exactly a year before this episode did ('Catdog' premiered on 4/4/1998 and this episode on 4/7/1999). The later aired about a month after this episode.
Answer: No, he did not. He is seen getting off the bus with a suitcase, so he must have not been home for a few days so there is no way he could have known.
Bowling255 ★