Frightened by their new teacher, Ava, Ellie and Griffin are not excited about the new school year. Their fear is replaced with curiosity about Miss Snoddy. Every day she wears old-fashioned clothes smelling of moth balls and lace-up, black leather shoes. The trio quickly learns their teacher knows a lot about American history. A peek into an old journal adds to the mystery. They discover personal notes about events such as the Boston Massacre and a friendship with Paul Revere. Unsure of what is going on, they sneak into her house in search of more clues. Finally, when Miss Snoddy sees them in class viewing a picture of her in a history book, she decides to tell them the secret she's been hiding. They are unaware of the adventures that await them!