Harold, Sid, and Stinky all moon Principal Wartz, but Arnold is blamed, even ...
Hey Arnold!
Season 4 Episode 9: Dinner for Four
Helga wants to show Arnold that she can be as sophisticated as Lila is by taking him, Gerald, and Phoebe out to dinner with a coupon she won. She devises a plan to get out of paying when she discovers they're at the wrong restaurant.