Discrepant Event: The Great Bowling Ball Float-Off

The concept of density is central to the study of science. Because of its importance, density is one of many physical properties that are studied in first-year chemistry and physical science courses. Determining the density of a solid or liquid is a routine laboratory activity in these classes, and is easily adapted to inquiry-based methods. In this activity students are to decide whether an assigned bowling ball will float or sink in water. They must make their predictions based on a mathematical determination, as they are not permitted to place the bowling ball in water until it is time to test their hypotheses. Students gain practice in various measurement techniques as well as calculations involving significant digits, unit conversions, and geometry formulae. Testing materials for this activity are available at no cost from local bowling alleys, and the measurement devices necessary are commonly found at home. Using household equipment permits students to extend their experimentation beyond the classroom to other solid objects. Since most students are familiar with the sport of bowling, and the results of this activity are surprising, this gives them a new perspective on a real-world experience. Disposal issues are not a concern since all the materials can be continually reused.