Description of the paper – e.g. topic, research question, objective, purpose, value, conceptual or theoretical framework, state of the art: In this paper I present a study of (1) students’ academic work and (2) the differences in the academic work of higher-and lower-achievers in fourth-grade math classroom. I propose to view the classroom as a task structure which determines opportunities to learn, and thus classroom effects. Opportunity-to-learn captures the notions of what content students are offered, and how that content is presented to them (McDonnell, 1995). I use Doyle’s (1983) powerful but underused ‘ecological’ framework to analyze the ‘academic tasks’ found in students’classroom work. Thus, the first part of the paper develops an analytical fraework capable of identifying the academic work being undertaken in a fourth-grade math classroom in an American school. The second part uses the framework in order to explore the mechanisms by which achievement differences are produced in one classroom. The following research questions guide this study: 1. How do I conceptualize the “tasks” of the math classroom? Doyle’s conceptualization of the classroom as a site for academic work framed in terms of tasks allows for the possibility of a range of different within-classroom task structures entailing different levels and kinds of academic work. A mapping of such differences onto the notion of opportunity to learn suggests a framework of understanding the mechanisms for the production of differences in learning outcomes within classrooms. Thus I ask: 1. What is the role of classroom tasks in the production of achievement differences? 2. Are there differences in the classroom tasks of higher and lower achievers? I investigate the following hypotheses concerning this second set of questions: 1. Higher-and lower-achieving students inhabit different task environments, with different implicit achievement outcomes. 2. Different task environments interact with lower- and higher-aptitude students in different ways.

Methodology or methods/research instruments or sources used: Observation and fieldnotes of a fourth-grade elementary school classroom in an American school provide the data for the empirical study. Following Stodolsky (1983), I map the classroom ecology and its structure of 'segments'. I then describe the patterns of academic tasks manifested in the segment structure. I then define specific opportunities to learn and the accountability frames directed at students nominated by the classroom teacher as higher-and lower- achieving students.

Conclusions or findings: It is the accountability regime created by the teacher rahter the manifest learning tasks that students undertake that determines the nature of ‘their academic work’. This accountability regime is determined by the teacher and was in its turn built from the mutual adjustments of expectations and responses on the part of the teacher and students- altough the teacher was largely unaware of what she was doing. Doyle’s language of task structures helped me to see that OTL and the segment proporties (engagement, attention, pacing and accountability regime) had significant implications for what students did in this mathematics class, and for students’ achievement. This finding invites us to think about ways in which teachers understand their classroom work. I conclude with the claim that the ecological framework for analyzing classrooms offered by Stodolsky (1983) and the focus on academic work offered by Doyle (1983) offer powerful lenses for thinking about teaching and in classrooms. This framework should be incorporated within the curriculum of teacher education.