Whopper Wiener Wednesday is an event that takes place in Peach Creek Jr. High's cafeteria every Wednesday. It was first introduced in "This Won't Hurt an Ed," where Eddy says, "It's Whopper Wiener Wednesday in the caf."
It's a special event revolving around hotdogs. It seems students are allowed double their normal servings. Not much is known about it. It has only been mentioned again through background posters (and the event may serve as the explanation for Eddy's numerous, quasi-infinite hotdog supply in "A Fistful of Ed"). A poster advertising the event is briefly seen during the scene where Jimmy and Sarah weenie-toast.
During Whopper Wiener Wednesdays, Rolf goes crazy for meat and is pretty much the only one who cares about it, with the possible exception of Ed. The menu for Whopper Wiener Wednesday appears to be hot dogs, French fries, the condiment(s) of your choice, and a drink.