|First Appearance||"Pilot episode" July 10, 1996|
Helga Geraldine Pataki is nine years old and in fourth grade. She constantly bullies her classmate Arnold, yet she does this to hide her true feelings of love for him. She is a talented writer and occasionally expresses interest in pursuing it as a career. She is neglected by her parents and calls them by their first names because she does not think they are worthy of being called "Mom" and "Dad". She resents her overachieving, perfectionist older sister, Olga. Once in a while Helga will show a very small amount of love for her sister. As in the episode "Olga Gets Engaged", when she intervenes on Olga's behalf, saving her from what would have been a bad marriage and "Big Sis" when she reveals her jealousy of Olga's relationship with Lila. Probably because of her dysfunctional home life, Helga is an insecure person and puts on a mean, and/or tomboyish front, making her the school bully. Helga's middle name never is revealed in the show except by her initial, but in a chat Craig Bartlett stated that the initial "G" stands for "Geraldine" and is a tribute to former Nickelodeon executive Geraldine Laybourne.
Helga appears as a playable character, along with Arnold, in Nicktoons Racing. She drives in a normal looking car and has two tracks based on their show.