This paper is focused on a relatively new emphasis in education research: the nature of academic work contained in the curriculum of elementary and secondary schools, how that work is organized and accomplished in classrooms, and what modifications in academic work are likely to increase student achievement. The paper is divided into two major sections. The first section is devoted to an analysis of the intellectual demands inherent in different forms of academic work. Of special importance in this section is the recent work on cognitive processes which underlie school tasks. The second section is directed to studies of how academic work is carried on in classroom environments. Particular attention in this section is given to the ways in which social and evaluative conditions in classrooms affect students' reactions to work. Each section contains an analysis of implications for improving the quality of academic work in classrooms and thus increasing student achievement. Also present is an extensive bibliography (21 pages). (JM)