Archimedes ran through the streets of ancient Greece shouting “Eureka!” when he realized how he could utilize his density and water displacement experiments to demonstrate that the king’s crown was made of pure gold. Students can discover Archimedes’ Principle for themselves with the inquiry strategy employed in this kit. Students place clay into containers totally filled with water. Accurate measurement of the displaced water will guide them to Archimedes’ Principle. Students will especially have fun when they use the same piece of clay to build a boat and then compare the amount of water being displaced. When cargo is added to the boats, student motivation will be high and discussion plentiful. Detailed student materials and teacher background materials are provided.