Most didactic lab experiments deal with the influence of temperature, concentration, pressure, surface area, and catalysts on chemical kinetics; however, few of them explore the influence of light radiation and the presence of inhibitor agents on reaction rates. In order to investigate the effects of the radiation source and the presence of inhibitors on chemical reaction rates, we developed a contextualized laboratory experiment to study qualitatively the degradation rate of food dyes using the Fenton reaction. The designed experiment was easily implemented and specially tailored for high school students. It demanded only household items, not requiring expensive reagents or equipment; therefore, it could be easily carried out in a simple high school lab setting. In addition, the didactic experimentation enabled students to address issues relating to chemical kinetics, reactivity of free radicals, antioxidant agents, the electromagnetic spectrum, and dye environmental pollution.