The schoolyard as a setting for teaching and learning is rarely the focus of chemistry education research. Therefore, a chemistry unit combining activities in the classroom and the schoolyard was designed to support preservice teachers' (PSTs) learning of redox chemistry. This study was conducted to investigate the PSTs' talk about redox chemistry as they identified, photographed, and explained phenomena in the schoolyard (i.e., university campus). Video data were collected from six groups of PSTs from two different teacher education institutions in Norway. Videos from two groups were selected for deeper analyses: one with PSTs who had specialized in chemistry during their secondary education and one with PSTs who had not. The groups' talk was analyzed with respect to (1) the types of talk, (2) the levels of chemistry displayed in the talk, and (3) the schoolyard phenomena that triggered the content-related talk.The talk was mostly exploratory, and the PSTs connected sub-micro-level redox chemistry to macro-level phenomena. Moreover, the PSTs noticed several phenomena in the schoolyard that triggered chemistry-related talk. Although the talk that developed occurred differently in the two groups, this study indicates that the schoolyard can provide opportunities for learning chemistry for learners with different formal backgrounds in chemistry.