Adam Sandler as Billy Madison

Bradley Whitford as Eric Gordon

Josh Mostel as Principal Max Anderson

Bridgette Wilson-Sampras as Veronica Vaughn

Darren McGavin as Brian Madison

Norm Macdonald as Frank

Mark Beltzman as Jack

Larry Hankin as Carl Alphonse

Theresa Merritt as Juanita

Dina Platias as Miss Lippy

Hrant Alianak as Pete

Vincent Marino as Cook

Christopher Kelk as Rollo the Janitor

Marc Donato as Nodding 1st Grader

Keith Cole as Penguin

Chris Mei as Penguin

Conor Devitt as O'Doyle (Grade 1)

Jared Durand as Scotty Logan (Grade 1)

Jessica Nakamura as Tricia Labonte (Grade 1)

Helen Hughes as 2nd Grade Teacher

Jacelyn Holmes as 2nd Grader

Jack Mather as Ted 'Old Man' Clemens

Claire Cellucci as Attractive Lady

Shane Farberman as Clown

Al Maini as Driver

Jared Cook as Ernie (Grade 3)

Christian Matheson as O'Doyle (Grade 3)

Kyle Bailey as Kyle

Vernon Chapman as Butler

Mandy Watts as Maid

Austin Pool as Dan (Grade 3)

Gladys O'Connor as Tour Guide

Marcia Bennett as 4th Grade Teacher

Diane Douglass as Nurse

Tim Herlihy as Architect

Frank Nakashima as Architect

Joyce Gordon as Lunch Lady

Jordan Lerner-Ellis as Pothead

Daniel Lerner-Ellis as Pothead

Robert Smigel as Mr. Oblaski

Melissa Korzenko as Nancy Connors

Colin Smith as O'Doyle (Grade 9)

Jeff Moser as Paul

Amos Crawley as Rod

Tex Konig as Crazy Person

Eduardo Gómez as Crazy Person

Tanya Grout as Joyce

Benjamin Barrett as Tenth Grader

Matthew Ferguson as Tenth Grader

Sean Lett as O'Doyle (Grade 12)

Stacey Wheal as Jennifer (Grade 3)

Shanna Bresee as Susan (Grade 3)

Michael Ayoub as Drama Teacher

Lawrence Nakamura as Lawn Guy

Gino Veltri as Rock Singer

James Downey as Principal

Bob Rodgers as Mr. O'Doyle

Margo Wladyka as Mrs. O'Doyle

Allison Robinson as Newswoman

Marcel Jean Gilles as Haitian Gardener

Suzanna Shebib as High School Girl

Justin Williams as 3rd Grader

Nicholas A. Catalano as 3rd Grader

Devon Codrington as 3rd Grader

Nicole Harrison as 3rd Grader

Lindsay Curran as 3rd Grader

Brandi Tower as 3rd Grader

Cassandra Forrester as 3rd Grader

Matthew Tempest as 3rd Grader

Michelle Toth as 3rd Grader

Craig MacIsaac as 3rd Grader

Tara Rooney as 3rd Grader

Robby Cavallari as 3rd Grader

Ryan Luis as 3rd Grader

Alanna Budhoo as 3rd Grader

Shomar Dejonge as 3rd Grader

Carmela Bigioni as 3rd Grader

Eric Aguilera as 3rd Grader

Kevin Le Roy as Jet Skier

Kelly Childerhose as Jet Skier

Ken Shires as Fire-eater

Steve Buscemi as Danny McGrath (uncredited)

Chris Farley as Bus Driver (uncredited)