Milo Coy

Stan

Jack Black

Grown Up Stan (voice)

Lee Eddy

Mom

Bill Wise

Dad

Natalie L'Amoreaux

Vicky

Josh Wiggins

Steve

Jessica Brynn Cohen

Jana

Sam Chipman

Greg

Danielle Guilbot

Stephanie

Zachary Levi

Kranz

Glen Powell

Bostick

Larry Jack Dotson

Grandfather

Mona Lee Fultz

Grandmother #1

Jennifer Griffin

Grandmother #2

Holt Boggs

Sam The Rocket Man

Samuel Davis

Pinball Buyer

Brian Villalobos

Bales

Chris Zurcher

Jack

David DeLao

Mr. St. George

Nick Stevenson

SIMSUP

Avery Joy Davis

Lisa (uncredited)

Christian Moran

Hoodlum (uncredited)

Keslee Blalock

AstroWorld Kid (uncredited)

P. Michael Hayes II

SIMSUP (uncredited)