This study investigated how simulations at the New Zealand earth science exhibition Earthworks could teach geological concepts. The introduction of a geoscience component in the New Zealand science curriculum, the development of science-technology centres and a funding opportunity provided the incentive for the development of Earthworks, which exhibits linked to the themes of the New Zealand science curriculum. For the designers of Earthworks, the exhibition was a challenge to provide an opportunity for both students and their teachers. This study looked at students’ interactions at the science centre and portrayed them as objectively as possible, including externally contributing factors. Therefore, information such as the ideas that the designers tried to portray through the exhibits or the attitude of the teachers towards earth sciences was just as important as how the students experienced the simulations. Although the literature provides discussion and definitions about learning in science centres, generally there has been less about the learning and teaching aspects of earth sciences in such settings. The aim of this study was to tie together many of the previous findings and apply them to the hypothesis that earth sciences can be taught effectively when they are supported by a simulation. This proposition was assessed by using a variety of methods: (1) analysis of observations of 118 students and 8 adult visitors to the earth science exhibition Earthworks; (2) content analysis of focus group interviews with 47 students and 37 teachers; (3) analysis of pre-questionnaires conducted with 156 teachers, 26 of which replied in a post questionnaire round; and (4) a document analysis that examined three documents. Findings of the investigation gave rise to five conclusions about the impact of earth science simulations at science centres: (1) it was discovered that a theoretical framework assists designers in conceptualisation and teachers in the implementation of the program; (2) several factors were identified that enhance the ability of a simulation to effectively communicate earth science concepts like: clear communication of concepts, clear demonstration of spatial and causal processes, the opportunity for the participant to make hypotheses and test them and a clear statement of the role of the participant. (3) The results of the study further showed that students would usually try to find a meaning for something they saw and make a judgement as to whether it is worth while pursuing. (4) The recognition of a concept displayed by using a simulation appears to happen in a similar sequence to that of learning to read. (5) The findings from this study suggest that the motivation for reading a label on a given exhibit is driven more by the agenda of the visitor than by any other factor such as readability. A central conclusion is that simulations have the potential to provide a useful tool for it to teach earth science concepts in the environment of a science centre, however it is vital for the success of such a learning tool to be carefully planned and tested before use.