The seventh graders wrapped up their unit on metric measurement by exploring the density of Diet Coke, which floats in a tank of water, versus that of “real” Coke, which sinks. The classes measured out 39 grams of sugar (the same quantity a 12 oz. can of Coca Cola Classic contains), and compared the sweetener mass to that of an artificial sweetener similar to the one in Diet Coke. Coke Zero, which floats higher than Diet Coke, was inferred by the students to have a density even closer to that of water than Diet Coke.