Through the chapters in this volume we learn about the research foci
and/ or questions that these classroom teachers are interested in
examining, the mathematics content through which they engaged their
students in these explorations, the data sources they used to make sense
of their focus and questions, and their roles in the research. An
overarching theme through all the chapters in this volume is the
learning and professional development that occurs through teacher
research. What these authors learned about student learning and their
own teaching practice far exceeded the focus of their particular
research questions. For some, the research validated their beliefs and
instructional practices; for others, it deepened or extended their
understanding of mathematics, or raised their expectations of students'
capabilities. For all, it is fair to say, their research increased their
awareness of how students come to know and understand mathematics, and
enabled them to gain insight into the complexity of teaching. Lampert
(2001) noted, "One reason teaching is a complex practice is that many of
the problems a teacher must address to get students to learn occur
simultaneously, not one after another" (p. 2). We, as readers, gain a
window into these teachers' research within and about the complexity of
classroom teaching.