Abstract
This chapter reports investigation on Taiwan middle school teachers’ collection of mathematical instructional tasks. Specifically, the analysis focuses on geometry tasks from a cognitive-complexity perspective. Six Taiwanese middle school teachers teaching at schools with different levels of mathematics performance participated in this study. The analysis showed that Taiwanese mathematics teachers included tasks from multiple sources, including textbooks, supplementary materials, tests, and tasks created by the teachers during classroom teaching. No matter which level the school’s mathematics performance is, teachers intended to collect tasks for classroom teaching that involved diagram complexity and problemsolving complexity. The analysis also showed that the better the school mathematics performance, the higher the cognitive complexity of tasks the teachers intended to collect. A further examination of the cognitive complexity of tasks situated in multiple sources indicated that tasks collected from non-textbook sources all had higher cognitive complexity than those from textbooks. Interviews with the teachers showed that they thought it was essential to afford students opportunities to learn how to solve cognitively complex tasks, even with those students who are in low mathematics-performance schools.