2023 Volume 28 Issue 2 Pages 77-97
The purpose of this paper is to develop a socially open-ended problem for high-school mathematics lessons with a focus on the nurturing and evaluation of the students’ critical thinking and to verify its effectiveness through practical lessons. This study aims to nurture critical thinking, defined as a broad sense to include mathematical problem solving in the real world. Here, the definition of “critical thinking” is “to propose solutions based on a mathematical model built on the students’ own values by identifying the problem beneath the superficial differences” and the “effort to improve the students’ own solutions by determining appropriateness and reliability of other people’s solutions” (Hattori, 2020, p.162). The study developed a lesson for the secondyear students in high school, with “propose a mayonnaise nozzle” as the theme. As a framework to evaluate students’ critical thinking, the study also developed rubrics. Through the practical lesson, students made full use of their mathematical knowledge they have acquired so far and solved the problem based on their individual values. In particular, the students were identified with an attitude to improve their solutions by observing and determining appropriateness and reliability of other people’s solutions. The study also suggested the possibility of evaluating critical thinking demonstrated by students through rubrics to a certain extent. On the other hand, “reviewing the definition of critical thinking in a broad sense in the context of mathematics education”, “necessity to analyze not only the worksheets but also multiple aspects, such as presentations, etc., in the rubric-based evaluation”, and “methods employed by the teacher in lessons where social values are shared” were identified as the issues to be addressed in subsequent studies.
