After her father's stroke, the offbeat Mona Gray gives up of all the things she likes expecting that her father will be better. When she is 20, her mother kicks her out and lies to her friend Ms. Gelband, a school principal, that Mona is a college graduate and qualified to teach third-grade mathematics, so the principal hires her. Once she settles in, Mona feels drawn to orphan Lisa Venus, and her odd behavior attracts the attention of teacher Ben Smith. One incident at school changes Mona's life for good.