An ethnographic study examined the personal and professional life experiences that contributed to a science teacher's beliefs about science and science teaching, and how these experiences interacted to affect the teacher's decisions about content literacy strategies. The teacher in question was a veteran of 16 years of teaching chemistry and mathematics at Taft High School, located in a mid-size midwestern town. Data were collected over an 18-month period. Primary data sources were seven formal, semi-structured interviews and daily informal teacher interviews. Results indicated that the personal and professional experiences and values that shaped the teacher's beliefs about science, science teaching, and using literacy activities can be described by the theme "doing what's right." As the teacher recounted her experiences, she talked of caring, respect, guidelines, and organization. She chose teaching and learning strategies because she believed that by helping students learn how to learn, she was "doing what was right" for her students. She chose literacy strategies that fostered organization in science thinking and learning. Findings suggest that pre-service and inservice teacher education programs should ask teachers to construct "autobiographical selves" to perceive and evaluate the complex factors that may influence their classroom decisions, and that educators need to closely examine the context of teachers' (and students') lives to make changes in education. (Contains 33 references.) (RS)