Frankie Muniz as Malcolm
Erik Per Sullivan as Dewey
Justin Berfield as Reese
Jane Kaczmarek as Lois
Bryan Cranston as Hal
Christopher Masterson as Francis
Craig Lamar Traylor as Stevie Kenarban
David Anthony Higgins as Craig Feldspar
James and Lukas Rodriguez as Jamie
Emy Coligado as Piama Tananahaakna
Kenneth Mars as Otto Mannkusser
Catherine Lloyd Burns as Caroline Miller
Daniel Von Bargen as Commandant Edwin Spangler
Cloris Leachman as Ida
Eric Nenninger as Eric Hansen
Karim Prince as Stanley Winn
Brenda Wehle as Lavernia
Evan Matthew Cohen as Lloyd
Kyle Sullivan as Dabney Hooper
Gary Anthony Williams as Abraham 'Abe' Kenarban
Will Jennings as Kyle
Meagen Fay as Gretchen Mannkusser
Hayden Panettiere as Jessica
Tania Raymonde as Cynthia Sanders
Merrin Dungey as Kitty Kenarban
Sandy Ward as Pete
Chris Eigeman as Lionel Herkabe
Arjay Smith as Ken Finley
Cameron Monaghan as Chad
Danny McCarthy as Hanson
Reagan Dale Neis as Nikki
Brittany Finamore as Alison
Julie Hagerty as Polly
Amy Bruckner as Zoe
Beth Grant as Dorene Hooper
Bea Arthur as Madame White
Christopher Lloyd as Walter
Laurie Metcalf as Susan
Jennette McCurdy as Daisy
Lisa Foiles as Mallory
Mimi Paley as Renee