Steele was born in Philadelphia, Pennsylvania. Her mother, Katherine A. High, is a hematology oncology physician at the University of Pennsylvania, and her father, George Steele, is an internal medicine physician specializing in nutrition who was on the faculty of the University of Pennsylvania School of Medicine.
Steele graduated with the class of 2006 from The Episcopal Academy a private school in southeast Pennsylvania. She graduated from Columbia University in 2011 with a Bachelor of Arts in Comparative Literature.
After her breakout role as Bernice in the 2004 film Spanglish, Steele continued acting, appearing on an episode of Law & Order and in the films: Mr. Gibb, which co-stars Hayden Panettiere, Tim Daly and Dan Hedaya. And Margaret, which co-stars Matt Damon, Matthew Broderick, Anna Paquin, Mark Ruffalo, and Allison Janney.
Steele was seen on the New York stage in an off-Broadway production of The Prime of Mission Jean Brodie, which ran for a few months at the Acorn Theater.
From 2007 to 2008 she appeared in the off-Broadway play Speech & Debate. From January to March 2012 she appeared in the off-Broadway play Russian Transport at the Acorn Theatre, playing the role of Mira.
She has also appeared in other off-Broadway and regional productions. In late 2014 Steele made her Broadway debut in The Country House by Donald Margulies, playing the granddaughter, Susie, opposite Blythe Danner.
Steele appeared in three episodes of The Good Wife in 2011 as Marissa Gold, the daughter of Eli Gold (Alan Cumming).
She reprised the role during season six in 2014.
