This paper presents findings from classroom observations of one teacher (Beth). It focusses on the development of conceptual understanding of fractions with her students, articulated in Kieren's sub-constructs (Kieren, 1980,1988), and Hansen's progressions (Hansen, 2005). The study covers three lessons within a six week unit. Findings from this study suggest there is a need for teachers to understand and teach a wider range of fraction constructs than appears to occur currently; how assessment data available might be used more effectively to plan quality lessons; and highlights the importance of a varied range of models to connect conceptual and procedural understanding of fractions.