The nature of knowledge needed for teaching elementary science and the development of such knowledge is a focus of ongoing research in science education. Internationally, there is a move to include scientific literacy as an aim of science education curricula. In order to teach such curricula teachers need two types of subject matter knowledge (SMK): knowledge of science and knowledge about science. Knowledge of science refers to the knowledge produced by science (substantive knowledge). Knowledge about science refers to the nature of science (NOS): the principles and means by which scientific knowledge develops and becomes accepted (syntactic or epistemic knowledge). In addition, teachers need to know "how" to teach both these kinds of SMK effectively (pedagogical content knowledge [PCK]). This case study analyses the practice of a New Zealand generalist elementary teacher using a framework developed from the literature based on Shulman's conceptualisation of teacher knowledge. It describes the nature and development of syntactic aspects of her SMK and PCK as she planned and taught a unit on science investigation. Analysis of student learning indicates some success in transfer of syntactic knowledge. The teacher used the limited connections she had with scientific communities of practice and documentation of scientific practice to develop her syntactic science knowledge. She applied strategies used in her general practice to teach syntactic aspects of science. Reflection on the effectiveness of these learning experiences built new PCK, supporting theories about the transformative development of PCK from other knowledge domains. Access to knowledge about the NOS is raised as a possible problem for generalist elementary teachers implementing curriculum with scientific literacy as a goal. (Contains 1 figure and 3 tables.)