The oxidation of iron is an important reaction due to its high economic impact. In this laboratory exploration, the total order of this reaction was determined using commercially available handwarmer packets that rely on the iron-oxygen reaction to generate heat. The active ingredient in the handwarmer packet is iron, which interacts with atmospheric oxygen once the packet is open to the atmosphere. Vernier oxygen gas sensor probes were used to monitor the oxygen in the reaction cell as a function of time. Transferrable skills, such as graphing and data analysis using spreadsheet software, were reinforced during data analysis. The experiment is simple to set up, uses materials that have no known hazards (hence a green chemistry approach), and provides students an opportunity to engage with a commonly used household product to investigate the kinetics of an important and familiar reaction.