What are the motifs in The Unexpected Mrs. Pollifax by Dorothy Gilman?

It may seem strange that this book has a coming of age idea considering that the main character is more than sixty years old as the book begins. Still, the book contains many elements of the coming of age theme, seen most clearly as Mrs. Pollifax interacts with people from her home in New Jersey. As the story opens, Mrs. Pollifax is clearly seen as a woman who is somewhat timid in the presence of Mrs. Heartshtorne. Mrs. Pollifax notes that whenever Mrs. Heartshorne talks to her, she feels as if she is a child in school and Mrs. Heartshorne is the teacher who is disappointed in her performance in math.