Agron attended Burlingame Intermediate School and Burlingame High School, where she was in the Homecoming Court, and played the part of Marty in Grease; she was also involved in set design, costumes, and painting. She has been dancing since the age of three, focusing mainly in jazz and ballet, and later began hip-hop dancing. Agron then fell in love with musical theater, and often performed in local and school productions. She played Dorothy Gale in The Wizard of Oz in fifth grade, and began teaching dance as a teenager. She says she was not "popular" in the stereotypical sense in high school, though she had many friends from different cliques around the school. As a teenager, Agron worked at a local boutique, where she "became enthralled with fashion," and was on her high school's yearbook committee.