Whalin was born in the Sunset District of San Francisco, California. His mother, Terry Villanueva, is a teacher and school administrator who owns and operates two L.A. area schools: The Learning Castle and La Cañada Preparatory. His father, Craig Whalin, is a real estate appraiser.[3] His parents divorced when he was seven years old and both remarried. He has a younger half-brother and an older stepbrother and stepsister.[citation needed]
He studied acting at the American Conservatory Theater (A.C.T.) in San Francisco, and attended Lowell High School. After years of commuting between Los Angeles and San Francisco, he and his mother relocated to L.A. permanently when he was fifteen years old. He completed his high school education through U.C. Berkeley's homeschooling program.
Whalin was cast as the young Daily Planet photographer Jimmy Olsen in the TV series Lois & Clark: The New Adventures of Superman from 1994 to 1997. Whalin said that initially the only fan mail he got on the show was from people complaining that he was not as good as Michael Landes (who played Olsen during the show's first season), and that it was not until around his fifth episode that he began to see an even mix of positive and negative fan reactions.[5] He enjoyed the role, though he said it often seemed limited to delivering exposition; a reoccurring motif of the series was that Lois and/or Clark would ask Jimmy to research a suspicious person or organization, and in a later scene Jimmy would rattle off the requested names, dates, addresses, and backstory.[6] When Whalin was first cast, the producers had planned a Jimmy Olsen-centric episode in which Jimmy heads to South America to look for his long-lost father,[4] but it was never produced, though the show did get Olsen-centric episodes in season 3 ("The Dad Who Came in From the Cold") and 4 ("AKA Superman").
Whalin quit acting in 2009 to work as a social studies/drama[7] teacher and administrator at The Learning Castle and La Cañada Preparatory, his mother's exclusive schools in the Los Angeles area.
