Abstract
Over the past decades, the major influence of mathematical instructional tasks on student learning has been recognized and studied. Mary Kay Stein and a group of colleagues, including Edward Silver proposed an analytical scheme known as the Mathematical Tasks Framework (MTF). They also identified the levels of cognitive demand specific to mathematical instructional tasks. The MTF presents the critical phases that describe the progression of mathematical tasks in classroom teaching and their influence on student learning outcomes. The levels of cognitive demand function as theoretical lens to examine mathematical instructional tasks through phases. In this chapter, we first introduce the MTF and the levels of cognitive demand. We then reviewed the literature developed based on the MTF and/or the levels of cognitive demand. The critical review showed three main trends, including research on teaching, research on teacher learning, and research on textbook analysis. Discussions and reflections on the critical review are also presented.