This is just one story, of course, but it suggests a possible way in which mathematical lives develop so that girls can be at the same time successful in mathematics but feel that they are not. The joint production by Sian and her teacher of limited opportunities for building knowledge may be repeated for some time, and may feed and be fed by assumptions about girls' and boys'"ways of knowing." There is some support for this analysis in the data reported by Creese et al. (2004). Although it is not their intention to analyze the following extracts in terms of approaches to knowing (rather, they are concerned with the ways that boys and girls use language and talk about collaboration in the classroom), the data suggest that in fact middle-class boys (the data was drawn from two middle-class schools) are positioned as creative or constructed knowers, in Becker's typology, whereas girls are positioned as separate knowers. Here we see their teacher comparing boys and girls: