As an infant, Bernstein immigrated to the United States from Poland with her parents. She graduated in 1911 from the Philadelphia School of Design for Women (now the Moore College of Art and Design). Bernstein also attended the Art Students League in New York, studying with William Merritt Chase. In 1917, she became one of the founding members of the Philadelphia Ten, a pioneering group of women artists.
Bernstein's style was largely modernist, focusing on urbanism and popular culture, painting Coney Island, cinemas, and public transit. She kept this style up, even as her popularity waned after the 1920s. The women's movement saw a revival in Bernstein's popularity, recognizing her contribution to American art from the early twentieth century. Critics often described her style as "masculine."
Bernstein's works are in the collection of the Jewish Museum, the Cape Ann Historical Association, the Museum of the City of New York, the National Museum of Women in the Arts, the Montclair Art Museum, and the Jack S. Blanton Museum of Art at the University of Texas. Bernstein died in 2002 a few weeks before her 112th birthday.