A teacher's orientation toward science teaching has been proposed as very influential to a teacher's pedagogical content knowledge (PCK) and teaching practice. Experienced teachers' orientation toward science teaching and its connections to their practice has not been well explored. Focusing on a unit about the periodic table, this study provides a case study using a respected, experienced high-school chemistry teacher's orientation toward science teaching to make sense of her observed teaching practice. Aspects of her practice, which aligned and misaligned with current recommendations for science teaching, were explored. Using observations, interviews, and class documents, the study concluded that the teacher's orientation toward science teaching was an appropriate way of understanding her teaching practice. While also being shown to be a useful tool for researchers, this case provides an example how a teacher's orientation toward science teaching could help in the development of professional development, specifically professional development for the recently released "Next Generation Science Standards."