The aim of this study was to analyze upper secondary school students’ reasoning of spontaneous redox reactions in three different situations, two situations in a school context and one authentic context. The study focused on students’ use of redox models, how they use the activity series of metals, which conception they have of the particles participating in the reaction and if there is any transfer of learning between the indoor and outdoor context. In the school context study 21 students participated in laboratory work about corrosion and a demonstration of a displacement reaction with zinc in a cupper sulphate solution. Ten of them were chosen for individual semi-structured interviews. The same students were interviewed a second time in an authentic context – a cupper statue on a corroded iron stand. Two individual and four two-groups interviews were then collected. The results indicate that the students used the activity series of metals in terms of noble and ignoble metals to explain corrosion. They exclusively used the electron model to explain redox reactions but some used partly the oxygen model in their reasoning in some of the redox reactions. The students showed an alternative conception in their explanation of the redox reaction of the laboratory work, compared to the scientific model. In the authentic situation the reasoning of the redox reaction became more scientific. The students’ reasoning around the displacement reaction seemed scientifically reinforced.