Background: Foundation phase teachers are not science specialists; however, they are expected to teach science. It is important that research determines where teachers face challenges in teaching science in order to assist them to bridge the gaps and to improve their competence in teaching science. Aim: The aim of this research was to explore teachers' implementation of the science curriculum. Setting: The research was conducted in a primary school in a province of South Africa. Four foundation phase teachers participated in the study. Methods: This interpretative, qualitative study used classroom observation, learners' workbooks and post-observation interviews to develop an understanding of teachers' science knowledge, their facilitation of hands-on science investigations as well as the nature of their interaction with learners in the science classroom. Results: The findings revealed that teachers were not competent in teaching science and when rated according to their profiles of curriculum implementation all four were allocated low scores. However, in-depth observations revealed that while teachers generally had poor science knowledge, they were competent in engaging learners through questions and activities. This pedagogic knowledge could have translated into pedagogic content knowledge should the teachers have attempted to spend more time preparing their science lessons to ensure that they mastered the necessary science content and science knowledge, as well as appropriate methodologies to teach science. Conclusion: Science education should be in the foreground in the foundation phase curriculum to encourage teachers to teach science as an integral part of the curriculum.