Adrien Brody
Psycho Ed
Matt Bush
Henry Burke
Sean Marquette
Travis Breaux
Colin Hanks
Brandon Ellis
Michael Chiklis
Dr. Leslie Gordon
Adhir Kalyan
Sebastian Saleem
Mykelti Williamson
Paranoid
Luis Chávez
Big Dave
Max Van Ville
Little Dave
Brett Kelly
Martin Gordon
George Back
Malcolm
Alicia Sixtos
Sharky Ovante
Andrew Wilson
Hippie Dude
Camille Mana
Dana
Erica Vittina Phillips
Tameka
Arcadiy Golubovich
Edwin Hunter
Julia Ling
Charlyne
Cody Longo
Chad
Mary Birdsong
Mrs. Gordon
Yeardley Smith
Computer Skills Teacher
Curtis Armstrong
Mr. Thompson
Alex Biats
Spelling Bee Rival
John Beard
Male News Desk Reporter
Barret Swatek
Female News Desk Reporter
Rhys Coiro
Vato
Wyatt Russell
Drug PSA Stoned Teenager
Mike Eshaq
Lead Terrorist
Heather Elizabeth Regan
Cheerleader who collides with Henry
Terri Lyn Rodriguez
Vivian
Robert Bailey Jr.
Jeffrey
Kelli Rasmus
Hippie Chick
Shirley Benyas
Older Female Donor
Wallace Bridges
African American Donor
Carl Harry Carlson
Donor #1
Randy Godwin
Donor #2
Mike Evans
Donor #3
Linda Boston
Head Nurse
Nadine Crocker
Emily Tooms
Clarence Smith
Chess Opponent
Ron Ayers
Stunned Lawn Bowler
Karl Murphy
Band Teacher
Rachel Quaintance
Angry Parent #1
Peter Tocco
Angry Parent #2
Mike Woods
Announcer
Kerry Birmingham
Female Reporter
Kevin Yon
Mr. Cavanaugh
Sammy A. Publes
Cook #1
Rene Santana
Cook #2
Billye Thompson
Cop #1
J. J. Soria
Rubin
David Herbst
School Security Guard
John O'Hurley
Drug PSA (voice)
John Stalberg Jr.
Grandpa Frodo - Ed's Frog (voice)
Heather Kleisner
Henry's Mom (voice)
D.B. Dickerson
Stoned High School Student (uncredited)
Sabrina Dungan
High School Student (uncredited)
Penny Gibbs
School Admin (uncredited)
Adam Lorenz
Dwayne Reynolds (uncredited)
Bill Lumbert
Concerned Parent (uncredited)
Misty Mills
Teacher (uncredited)
Jerry Reid
High School Student (uncredited)
Steven Sutherland
Academy Student (uncredited)
Joe Tinpan
Terrorist (uncredited)
Michael Vartan
Calculus Teacher (uncredited)
Kathi J. Moore
Librarian
Trey Livingston
Student (uncredited)