Roberta, a young violin teacher living in Greece (Streep), loses her husband to her best friend and moves with her two boys back to the States. Eventually the trio moves to New York to stay with Roberta's old high school crush, Brian Sinclair (Quinn).
Using Brian's connections, she's given a teaching job in Harlem by the school principal (Bassett). At first her class gives her a hard time, but soon she is able to make musicians out of all her pupils. Based on a true story, Roberta leads her group of young students through their studies, against odds that include the closing of the music department in their school, well enough for them to eventually perform at Carnegie Hall.