Although research from a developmental/psychological perspective indicates that many children do not have a scientific understanding of living things, even by the age of 10 years, little research has been conducted about how students learn this science topic in the classroom. This exploratory research used a case-study design and qualitative data-collection methods to investigate the process of conceptual change from ontological and social perspectives when Year 1 (5- and 6-year-old) students were learning about living things. Most students were found to think about living things with either stable, nonscientific or stable, scientific framework theories. Transitional phases of understanding also were identified. Patterns of conceptual change observed over the 5-week period of instruction included theory change and belief revision as well as reversals in beliefs. The predominant pattern of learning, however, was the assimilation of facts and information into the students' preferred framework theory. The social milieu of the classroom context exposed students' scientific and nonscientific beliefs that influenced other individuals in a piecemeal fashion. Children with nonscientific theories of living things were identified as being least able to benefit from socially constructed, scientific knowledge; hence, recommendations are made for teaching that focuses on conceptual change strategies rather than knowledge enrichment.