Justin Long as Bartleby Gaines

Jonah Hill as Sherman Schrader

Blake Lively as Monica Moreland

Adam Herschman as Glen

Columbus Short as Hands

Maria Thayer as Rory

Lewis Black as Uncle Ben

Jim O'Heir as Mr. Schrader

Mark Derwin as Jack Gaines

Ann Cusack as Diane Gaines

Hannah Marks as Lizzie Gaines

Robin Lord Taylor as Abernathy

Diora Baird as Kiki

Lisa Gleave as Kiki's Best Friend

Joe Hursley as Maurice / The Ringers

Jeremy Howard as Freaky Student

Anthony Heald as Dean Van Horne

Ross Patterson as Mike McNaughton

Sam Horrigan as Mike Welsh

Travis Van Winkle as Hoyt Ambrose

Kaitlin Doubleday as Gwynn

Kellan Lutz as Dwayne

Brendan Miller as Wayne

Chantelle Tibbs as Confused Kid

Skyler Stone as S. H. Student in Hallway

Darcy Shean as Mrs. Schrader

Brian Powell as Economics Teacher

Scott Adsit as Drop-off Dad

Lindy Loundagin as Drop-off Mom

Steve Little as Desk Clerk

Parker Quinn as Frat Guy

Artie Baxter as Mike Chambers

Greg Sestero as Frat guy (uncredited)

Sara Jean Underwood as Girl By Pool (uncredited)

Alejandra Gutierrez as Kiki's Best Friend

Yorke Fryer as S. H. Student in Hallway

James Taku Leung as S. H. Student in Hallway

Jay Harik as Family Friend

Mathew Vigil as Shoe Store Boy

Debbon Ayer as Shoe Store Mother

Carla Jimenez as Shoe Store Manager

Ned Schmidtke as Dr. J. Alexander

Tim Bagley as Vice Principal Matthews

Ray Santiago as Boy Going to Princeton

Margaret Travolta as Academic Counselor

Ethan Hova as Male Graduate (scenes deleted)

Criscilla Anderson as Go Go Dancer

Larke Hasstedt as Go Go Dancer

Meredith Giangrande as Glen's Party Girl

Kate French as Glen's Party Girl

Zoe Di Stefano as S. H. Testimonial Student

David Carmon as S. H. Testimonial Student

Armen Weitzman as S. H. Testimonial Student

Christopher Khai as S. H. Testimonial Student

Jamie Leffler as Fake ID Kid

Wendy Rodriguez as Fake ID Kid

Richard Alan Brown as Fake ID Kid

Mylika Davis as Fake ID Kid

Laurie Meghan Phelps as Fake ID Kid

Portis Hershey as Fake ID Kid

Joseph Stiteler as The Ringers

Asher Gold as Frat Guy