Teo Halm was born in Los Angeles, California. His parents are both Jewish; his mother's family is from France and Morocco and his father is Australian, with British/Czech forebears.[2][3]
Halm grew up performing in theater, doing "The Sound of Music" and "The Music Man".[4] His father posted a picture of Halm on the talent website newfaces.com, attracting the attention of a producer for the PBS series Nova.[5] In 2009 he was cast as a Neanderthal boy. [6] In 2010 he was hired to play "Will Campbell" a fictitious UCLA spokesperson in a fund-raising e-solicitation to UCLA alumni.[7]
In 2012 Halm played the lead in a short coming of age film, "Waltham Vanguard", written and directed by Bill Barker, Halm played opposite Jaime P. Gomez of Nash Bridges fame.[8] In 2013 he was cast in the Disney Channel Boy Meets World follow-up series Girl Meets World as Cory (Ben Savage) and Topanga's (Danielle Fishel) son Elliot. In 2014 he starred as vulnerable foster child Alex in the sci-fi fantasy film Earth to Echo. He will play Frank Sullivan, Charles Bukowski's childhood best friend, in the upcoming James Franco-directed movie Bukowski.[9] He was also cast in a supporting lead role as Alex, a rebellious skater kid, in the upcoming movie Memoria