Within a major numeracy project, there were marked differences in achievement between classes, which, as reported in Sullivan and McDonough (2002), we attribute to the teachers. To gain insights into the practices of effective teachers, six case studies of highly effective teachers at the Prep (first year of school) to Grade 2 level were conducted. This paper shares the research methodology and insights into the practices of the case study teachers. It suggests that the description of the practices of effective teachers can inform the work of those involved in teacher education. (Contains 1 figure.) [For complete proceedings, see ED500858.]