When filming was taking place, Jon Heder was 25.
Rachel McAdams was 25 at the time of filming.
Julia Stiles was 17 at the time.
He was 27 at the time of filming.
Alicia Silverstone was actually one of the only cast members in her teens, and was 18 at the time.
When filming started in March 2009, Ellen Wong was 24.
Newton-John was 28 when filming began and turned 29 during the film's production.
Logan Lerman wasn't that much older than his character, aged 19 when filming for The Perks of Being a Wallflower took place.
Anna Kendrick was 25 during the filming of Pitch Perfect.
McKenzie was cast for the role in 2003, when he was 24.