Zac Efron character Mike O'Donnell (Teen)
Leslie Mann character Scarlett O'Donnell (Adult)
Matthew Perry character Mike O'Donnell (Adult)
Michelle Trachtenberg character Maggie O'Donnell
Allison Miller character Scarlett (Teen)
Thomas Lennon character Ned Gold
Sterling Knight character Alex O'Donnell
Kat Graham character Jamie
Tyler Steelman character Ned Gold (Teen)
Tiya Sircar character Samantha
Melissa Ordway character Lauren
Josie Loren character Nicole
Jim Gaffigan character Coach Murphy
Collette Wolfe character Wendy
Adam Gregory character Dom
Hunter Parrish character Stan
Mario Cassem character Samir
Melora Hardin character Principal Jane Masterson
Brian Doyle-Murray character Janitor
Tommy Dewey character Roger
Lorna Scott character Secretary
Kodi Kitchen character Hostess
Diana Maria Riva character Judge
Ellis E. Williams character Bailiff
Ed Ackerman character School Cop
Will Schaub character Referee
Loren Lester character Mike's Lawyer
Nicole Sullivan character Naomi
Margaret Cho character Mrs. Dell
Larry Poindexter character Dean
Bubba Lewis character Dorky Kid (Ned's Party)
Chris Valenti character Syracuse Scout (1989)
G. Lane Hillman character Kevin (1989)
Hope Riley character Girl (Wyatt)
Jeanine Jackson character Scarlet's Lawyer
Gregory Sporleder character Ohio Scout
Keith Oney character Guy in Crowd
Leonard Wu character Kid (Office)
Liana Blackburn character Cheerleader (1989)
Lindsay Taylor character Cheerleader (1989)
Shelby Rabara character Cheerleader (1989)
Danielle E. Hawkins character Cheerleader (1989)
Katrina Norman character Cheerleader (1989)
Rhapsody Violetti character Cheerleader (1989)
Tiana Brown character Cheerleader (1989)
Taisha Monique Clark character Cheerleader (1989)
Vanessa Lee Chester character Cheerleader
Tyne Stecklein character Cheerleader
Jordan Schatz character Mr. Adams
Jesse Heiman character Mascot (uncredited)