Invader ZIM (2001)

Season 1: Episode 25

The skool is holding a candy drive in order to get some finances, in which the individual who sells the most chocolate bars will get a secret mystery prize. Zim becomes interested and he attempts to find a way to sell the most chocolate bars, which causes Dib to get into the contest in order to gain a defeat over Zim. Zim soon realizes, however, that he may have to take drastic measures in order to sell more candy bars than Dib.