Teaching complex chemistry concepts such as kinetics using inquiry-based learning techniques can be challenging in a high school classroom setting. Access to expensive laboratory equipment such as spectrometers is typically limited and most reaction kinetics experiments have been designed for advanced placement (AP) or first-year undergraduate courses. Therefore, we developed a new and inexpensive laboratory experiment specially tailored for high school students. The activities include in situ monitoring of iodide oxidation using individual UV-visible spectrophotometers, data analysis with a spreadsheet, and interpretation. The experiment introduces chemical kinetics, offers practice problems, and teaches students the technique of flooding to acquire data and make connections with reaction mechanisms based on trends observed in the rate constants. The exercise was successful in solidifying the concepts of rates, rate laws, reaction order, and their relation to mechanistic studies. The provided handout and notes are tailored to help high school science teachers implement the Next Generation Science Standards in their classrooms.