One way to show students that they can “do” science is to have them use an observable event to generate a relationship that can be used as a predictive tool. If that relationship can be quantified using “curve-fitting” and simple algebra, an equation describing the relationship can be created. To illustrate this concept in the classroom, teachers can have students investigate the inverse-square law through a simple experiment. By using readily available and inexpensive apparatus, students learn by demonstrating the quantitative relationship between light intensity and distance.