Tradition tells us that King Hiero II was suspicious about the purity of the gold in his crown and asked Archimedes to find a way to determine if it was pure gold or alloyed with silver. Solving the problem seemed to be impossible because in those days - the 3rd century B.C. - nothing was known about chemical analysis. One day Archimedes was thinking about the problem while taking a bath. As he lay floating in his bathtub, he thought about his weightless body. Suddenly he realized that all bodies lose a little weight when placed in water, and the bigger the volume, the more weight they lose. He realized that a given weight of gold would displace less water than an equal amount of silver, which is less dense than gold. Archimedes shouted "Eureka! Eureka! (I have found it!)" and rushed out into the streets of Syracuse naked to announce the discovery. Today the effect he observed is called Archimedes' Principle.

Your discovery of Eureka! will send you shouting "I have found it!". This resource for adult basic education instructors will allow you to search the Eureka! database and discover lessons and resources that have been used successfully by ABLE instructors with their students. Then you can try them out in your classroom. The database includes resources for planning instruction, standards based lesson plans, trade books and teaching strategies.