Four boys design and build a thirty-foot yawl and undertake an extended voyage through lakes, rivers, canals, and along the Gulf and Atlantic coasts. They learn seamanship and boatcraft while confronting the practical demands of construction, navigation, and maintenance. Their journey includes encounters with ice and freezing rigging, heavy gales, near-sinking and grounding episodes, interactions with marine life, and periods of being stranded or detained, balanced by port calls, local sights, fishing, and small victories. The narrative blends episodic adventure with technical detail and youthful resourcefulness, concluding with the crew’s eventual homeward return.