Anton Yelchin (Charlie Bartlett)
Robert Downey, Jr. (Principal Gardner)
Hope Davis (Marilyn Bartlett)
Kat Dennings (Susan Gardner)
Tyler Hilton (Murphy Bivens)
Mark Rendall (Kip Crombwell)
Megan Park (Whitney Drummond)
Jonathan Malen (Jordan Sunder)
Derek McGrath (Superintendent Sedgwick)
Stephen Young (Dr. Stan Weathers)
Ishan Dave (Henry Freemont)
Dave Brown (Officer Hansen)
Eric Fink (Thomas)
Noam Jenkins (Dean West)
Lauren Collins (Kelly)
Annick Obonsawin (Daisy)
Sarah Gadon (Priscilla)
Aubrey Graham (A/V Jones)
Michael D'Ascenzo (Scott)
Dwayne McLean (Bus Driver)
Quancetia Hamilton (Mrs. Albertson)
Richard Campbell (Dr. Sam Costell)
Kim Roberts (Dr. Linda Jenkins)
David Fraser (Dr. Jacob Kaufmann)
Marvin Karon (Dr. P. Sarossy)
Brendan Murray (Dorm Head)
Abigail Bernardez (Cheerleader #1)
Laura Jeanes (Cheerleader #2)
Annamaria Janice McAndrew (Cheerleader #3)
Amelia Tenttave (Len's Girlfriend #1)
Annabelle Singson (Len's Girlfriend #2)
Julia Cohen (Receptionist)
Abby Zotz (Kip's Mom)
Spiral Beach (Vocalists)
Maddy Wilde (Spiral Beach)
Airick Woodhead (Spiral Beach)
Dorian Wolf (Spiral Beach)
Daniel Woodhead (Spiral Beach)
Dylan Taylor (Len Arbuckle)
Jake Epstein (Dustin Lauderbach)