Each group needs:

• ruler
• graduated cylinder marked in milliliters (alternatively, provide a 2-liter bottle with the top cut off and a ruler so students can measure displacement in cm and calculate volume)
• scale (can be digital), to measure mass in grams
• known objects of a variety of materials, such as wood, steel, aluminum, plastic, glass, Styrofoam, water and oil; these objects can be found (glass marbles, steel marbles, wood blocks, etc.) or cut to appropriate size; find items in your home, school shop or hardware store
• irregularly shaped "mystery object" of unknown material; make it the same material as one of the known objects, but irregular in shape and masked with paint or tape to conceal its identity
• 4 plastic 500-ml drinking bottles
• aluminum foil, 1 sheet
• Eureka - Archimedes Principle Worksheet 1, one per student
• Eureka - Archimedes Principle Worksheet 2, one per student