Andrew Lawrence

T.J. Detweiler (voice)

Rickey D'Shon Collins

Vince La Salle (voice)

Pamela Adlon

Spinelli (voice)

Ashley Johnson

Gretchen Grundler (voice)

Jason Davis

Mikey Blumberg (voice)

Courtland Mead

Gus Griswald (voice)

April Winchell

Ms. Finster / Mrs. Detweiller (voice)

Dabney Coleman

Principal Peter Prickly (voice)

Ryan O'Donohue

Digger Dave / Randall (voice)

Robert Goulet

Mikey's Singing Voice (voice)

Melissa Joan Hart

Becky (voice)

Peter MacNicol

Fenwick (voice)

Tony Jay

Dr. Rosenthal (voice)

James Woods

Dr. Phillium Benedict (voice)

Andrea Martin

Lunchlady Harriet (voice)

Tress MacNeille

Lunchlady Irma / Ms. Lemon / Opera Director / Dr. Steinheimer (voice)

Nicholas Turturro

Cop #1 (voice)

Kevin Michael Richardson

Cop #2 (voice)

Dan Castellaneta

Guard #1 (voice)

Diedrich Bader

Guard #2 (voice)

Kath Soucie

Counselor (voice)

Charles Kimbrough

Mort Chalk (voice)

Robert Stack

Superintendent (voice)

Ken Swofford

Coach (voice)

Francesca Marie Smith

Ashley B / Swinger Girl / Upsidedown Girl (voice)

Erik von Detten

Captain Brad Lawson (voice)

Paul Willson

Coach Kloogie / Mr. Detweiler (voice)

Patrick Renna

Jordan (voice)

Anndi McAfee

Ashley A (voice)

Lane Toran

King Bob (voice)

Rachel Crane

Ashley Q (voice)

Klee Bragger

Digger Sam (voice)

R. Lee Ermey

Colonel O'Malley (voice)

Clyde Kusatsu

Mr. Yamashiro (voice)

Clancy Brown

Bald Guy (voice)

Allyce Beasley

Miss Grotke (voice)

Gregg Berger

Tech #1 (voice)

E. G. Daily

Cap'n Sticky (voice)

Ron Glass

Dr. Lazenby / Tech #2 (voice)

Mark Robert Myers

Technician (voice)

Phil Proctor

Golfer #2 / Scientist #2 (voice)

Justin Shenkarow

Soldier Kid / Wrestler Kid (voice)

Michael Shulman

Hustler Kid (voice)

Katey Sagal

Mrs. Flo Spinelli (voice) (uncredited)