Francesca Marie Smith
Helga Pataki (voice) (186 eps)
Jamil Walker Smith
Gerald Johanssen (voice) (186 eps)
Dan Castellaneta
Grandpa Phil (voice) (163 eps)
Justin Shenkarow
Harold Berman (voice) (149 eps)
Anndi McAfee
Phoebe Heyerdahl (voice) (111 eps)
Christopher Walberg
Stinky Peterson (voice) (88 eps)
Phillip Van Dyke
Arnold (voice) (76 eps)
Spencer Klein
Arnold (voice) (73 eps)
Olivia Hack
Rhonda Wellington Lloyd (voice) (66 eps)
Lane Toran
Arnold (voice) (56 eps)
Sam Gifaldi
Sid (voice) (47 eps)
Blake McIver Ewing
Eugene Horowitz (voice) (42 eps)
Craig Bartlett
Brainy (voice) (42 eps)
Tress MacNeille
Grandma Gertie (voice) (33 eps)
Kath Soucie
Miriam Pataki (voice) (28 eps)
Steve Viksten
Oskar Kokoshka (voice) (27 eps)
Maurice LaMarche
Big Bob Pataki (voice) (27 eps)
Dom Irrera
Ernie Potts (voice) (24 eps)
Dan Butler
Mr. Simmons (voice) (24 eps)
David Wohl
Principal Wartz (voice) (21 eps)
Ben Diskin
Eugene Horowitz (voice) (19 eps)
Baoan Coleman
Mr. Hyunh (voice) (18 eps)
Adam Wylie
Curly Gammelthorpe (voice) (14 eps)
James Keane
Mr. Green (voice) (13 eps)
Lou Rawls
Harvey (voice) (12 eps)
Christopher Castile
Eugene Horowitz (voice) (9 eps)
Mary Scheer
Suzie Kokoshka (voice) (9 eps)
Nika Futterman
Olga Pataki (voice) (6 eps)
Danica Ivancevic
Sabrina (voice) (6 eps)
Lauren Robinson
Nadine (voice) (5 eps)
Marcus Toji
Park (voice) (5 eps)
Rick Fitts
Mr. Johanssen (voice) (5 eps)
Avriel Epps
Timberly Johanssen (voice) (5 eps)
Jordan Warkol
Chocolate Boy (voice) (5 eps)
John Mariano
Vic / Morrie (voice) (4 eps)
Shari Belafonte
Mrs. Johanssen (voice) (4 eps)
Michael Bacall
Torvald (voice) (4 eps)
Joey Paul Jensen
Woman (voice) (4 eps)
Jarrett Lennon
Eugene Horowitz (voice) (4 eps)
Tony Jay
Rex Smythe-Higgins (voice) (4 eps)
Ashley Buccille
Lila Sawyer (voice) (4 eps)
Tim Wiley
Edmund (voice) (4 eps)
Rick Corso
Dino Spumoni (voice) (3 eps)
Jim Belushi
Coach Wittenberg (voice) (3 eps)
Carlos Alazraqui
Minion (voice) (3 eps)
Lisa Fuson
Movie Woman (voice) (3 eps)
Danielle Judovits
Patricia "Big Patty" Smith (voice) (3 eps)
Maria Bamford
Mayor Dixie / Stinky's Grandma (voice) (3 eps)
Elizabeth Ashley
Mrs. Vitello (voice) (2 eps)
Frank Martorana
Burt (voice) (2 eps)
Mark Hamill
Cop (voice) (2 eps)
Vincent Schiavelli
Mr. Bailey (voice) (2 eps)
Caroline Aaron
Landlady (voice) (2 eps)
Billy Riback
Announcer / PSA Guy (voice) (2 eps)
Lacey Chabert
Ruth P. McDougal (voice) (2 eps)
Ron Perlman
Mickey Kaline (voice) (2 eps)
Elliott Gould
Rabbi Goldberg (voice) (2 eps)
Cathy Moriarty
Tish Wittenberg (voice) (2 eps)
Joey Stinson
Rex Smythe-Higgins III (voice) (2 eps)
Mary Gross
Shelley (voice) (2 eps)
Lori Alan
Rhonda's Mother (voice) (2 eps)
Victor Samuel Lopez
Lorenzo (voice) (2 eps)
Bronson Pinchot
Director / Chauffeur (voice) (2 eps)
Gregg Berger
Lucky / Worker #1 (voice) (2 eps)
Candi Milo
Cherice (voice) (2 eps)
Mayim Bialik
Maria (voice) (1 eps)
Brian Doyle-Murray
Lasombra (1 eps)
Davy Jones
Himself (1 eps)
Michael Levin
Ray Doppel (voice) (1 eps)
Steven Hartman
Curly (voice) (1 eps)
Danny Cooksey
Stoop Kid (voice) (1 eps)
Pamela Hayden
Connie (voice) (1 eps)
Michael Donovan
Maria's Dad / Cabby (voice) (1 eps)
Quinton Flynn
Man #1 (voice) (1 eps)
Christine Ebersole
Lana Vail (voice) (1 eps)
Jim Lang
The Mad Engineer (voice) (1 eps)
Danny Strong
Teen #1 / Teen #2 (voice) (1 eps)
Hiep Thi Le
Mai Hyunh (voice) (1 eps)
Grant Gelt
Tucker Wittenberg (voice) (1 eps)
Max Casella
Tony B. / Philly D. (voice) (1 eps)
Kevin Michael Richardson
Blind Man / Newscaster (voice) (1 eps)
DeeDee Rescher
Torvald's Mother (voice) (1 eps)
Ben Aaron
Jamie O Johanssen (voice) (1 eps)
Joe Purdy
Mr. Purdy (voice; uncredited) (1 eps)
Angie Jaree
Big Bob Jingle Singer (voice) (1 eps)
Michael Fishman
Joey Stevenson (voice) (1 eps)
David L. Lander
Sam the Sewer King (voice) (1 eps)
Lloyd Sherr
Berlitz Teacher / Stylist (voice) (1 eps)
Julia Louis-Dreyfus
Miss Felter (voice) (1 eps)
Jimmy Peterson
Teenage Bully (voice) (1 eps)
Daniel Stern
Mr. Packenham (voice) (1 eps)
Harvey Korman
Don Reynolds (voice) (1 eps)
Alan Paul
Dino Spumoni (singing voice) (1 eps)
John Garry
Lieutenant Major Goose (voice) (1 eps)
Kathy Najimy
Madame Blanche (voice) (1 eps)
Marty York
Mickey the Weasel / Fifth Grader #1 (voice) (1 eps)
John Schuck
Wally / Announcer (voice) (1 eps)
Clancy Brown
Dan (voice) (1 eps)
John Rubano
Sherm (voice) (1 eps)
George Takei
Phoebe's Father (voice) (1 eps)
Jean Smart
Phoebe's Mother (voice) (1 eps)
Carol Kane
Emily Dickinson Trophy (voice) (1 eps)
Jamie Farr
Mr. Wacko (voice) (1 eps)
Sam McMurray
Robbie Fisher (voice) (1 eps)
Ashley Tesoro
Fifth Grader (voice) (1 eps)
Jer Adrianne Lelliott
Little Kid (voice) (1 eps)
Randy Travis
Travis Randall / Mr. Hyunh's Singing (voice) (1 eps)
Hari Oziol
Boy in Crowd (voice) (1 eps)
Wendy Hammers
Jackie Lee (voice) (1 eps)
Peter Scolari
Doug LeSham (voice) (1 eps)
Christian Mena
Ronnie Matthews (singing voice) (1 eps)
Steve Fitzpatrick
Floyd / Slim (voice) (1 eps)
Joseph Ashton
Iggy (voice) (1 eps)
Jane Carr
Inga (voice) (1 eps)
Moira Quirk
Woman / Kid #3 (voice) (1 eps)
Mitzi McCall
Pearl Simmons (voice) (1 eps)
Rose Marie
Agatha Caulfield (voice) (1 eps)
Jessica Sodd
Marcy (voice) (1 eps)
Tim Curry
Mr. Leichliter (voice) (1 eps)
Josh Ryan Evans
3rd Grader (voice) (1 eps)
Kyle Gibson
Crony (voice) (1 eps)
Cameron Van Hoy
Big Gino (voice) (1 eps)
Phil LaMarr
Jamie O Johanssen (voice) (1 eps)
Laraine Newman
Librarian / Kid (voice) (1 eps)
Phyllis Diller
Mitzi (1 eps)