Whalin has been working as an actor since the age of eleven, when he debuted in the title role of the play The Little Prince at San Francisco's Victoria Theatre. He starred in the 1993 CBS Schoolbreak Special production Other Mothers for which he won a Daytime Emmy for his portrayal of a son with lesbian parents. He went on to star in Miracle at Midnight opposite Mia Farrow and Sam Waterston. He also auditioned to play Billy Loomis in Scream.