At Lake Nipigon, Canada, a native boy carves a wooden model of an Indian in a canoe. On its side he roughly carves the words "Please put me back in the water. I am Paddle-to-the-Sea" and sets it free to travel the Great Lakes to the Atlantic ocean. The story follows the progress of the little wooden Indian on its journey. It is picked up several times, but the inscription is always obeyed. Once a man finds the inscription very worn and adds a metal plate bearing the same words. It traverses all five Great Lakes (including going over Niagara) and the St. Lawrence River, finally after many years arriving at the Atlantic Ocean. Its maker, now a grown man, is working in one of the Atlantic ports and witnesses it being picked from the water for the last time. He recognizes it, but does not lay claim to it, and the book ends with his words of pride, spoken only to himself.
Each movement of the canoe is celebrated by a short chapter, suitable for reading aloud to a child and decorated with black-and-white sketches and at least one full-page watercolor. The sketches accompany the larger story and tell smaller narrative stories of their own: for example, one sketch demonstrates how a sawmill works by visually outlining the progress of a log of timber towards a mechanical saw.