Why the details matter: Learning from Japanese Kyouzai kenkyuu

Have you ever heard someone say, “It’s exactly the same question, just with different numbers”? Sometimes a teacher might say this about a practice test or a set of exercises in a textbook. The implication is that the details of the numbers make no substantive difference to the problem. In mathematics task design, careful thought is not always given to the particular numbers used in questions; in some circumstances, these might even be randomly computer-generated. However, in Japanese mathematics teaching, the numbers used in questions (and the details in general) are taken extremely seriously. In this article, we will explain why the details of tasks matter so much. We will show across four mathematics topics with different ages of students how the detailed choices of examples can be critical for students to learn what is intended.