The science of solubility : using reverse engineering to brew a perfect cup of coffee

The Next Generation Science Standards call for the integration of science and engineering. Often, the introduction of engineering activities occurs after instruction in the science content. That is, engineering is used as a way for students to elaborate on science ideas that have already been explored. However, using only this sequence of instruction communicates a limited view of the relationship between science and engineering. In this article, we focus on the process of reverse engineering, and we provide a model 5E lesson in which we flip the typical science-to-engineering sequence and, instead, use principles of engineering design as a springboard from which to develop scientific concepts. Specifically, students use principles of engineering to deconstruct already engineered devices (i.e., different types of coffeemakers) in an effort to propose scientific explanations (i.e., factors affecting solubility) for the design features. These proposed explanations are then tested by isolating individual variables (e.g., solute size, temperature of solution) and testing the results. Students are provided whole coffee beans, grinders, water of different temperatures, timers, and apparatus for brewing samples of coffee and then test the effects of changing the variables by tasting, observing, or quantifying results of the individual samples.