# Triangle Based Scaffolding for Trigonometric Reasoning

## Published by The International Journal of Science, Mathematics and Technology Learning

Format Price
Article: Print \$US10.00
Published online: May 19, 2014 \$US5.00

Trigonometry is an essential branch in mathematics education. It has been claimed that trigonometry students instructed through use of triangles will face difficulties in picturing the behavior of the trigonometric functions, and consequently, fail to apprehend them. This study elaborates on notions about the effects of dynamic images illustrating angle variation using an adjustable triangle tool to scaffold trigonometric reasoning. We demonstrate how the scaffolding tool can help students develop reasoning about trigonometric functions. Findings from interviews with non-formal education students showed that the adjustable triangle tool allowed students to better understand trigonometric ratios by means of visualization of the angle variation. As a consequence the students showed increased reasoning, leading to improvements in trigonometric understanding. Our findings suggest that students’ difficulties of relating the measured angle to a trigonometric function may be due to the use of a static triangle, which does not support imagination and does not provide students with an effective foundation for reasoning. In conclusion, we have reason to believe that our teaching tool may benefit trigonometry instructions.

Keywords: Pedagogy, Mathematics, Non-formal Education, Trigonometry

The International Journal of Science, Mathematics and Technology Learning, Volume 20, Issue 3, May 2014, pp.99-109. Article: Print (Spiral Bound). Published online: May 19, 2014 (Article: Electronic (PDF File; 945.627KB)).

# Dr Artorn Nokkaew

Doctoral Student, Institute for Innovative Learning, Institute for Innovative Learning, Mahidol University, Nakhon Pathom, Thailand

Artorn Nokkaew is presently a Ph.D. candidate in Science and Technology Education at Mahidol University, NakhonPathom, Thailand. Also, he has worked for non-formal education since 2009. It was this experience that inspired his interest in non-formal education. His current works are in both scientific and educational fields. His research interests focus on genetic algorithm based optimization, mathematics education and non-formal education. He received B.Sc. degree in computer science from UdonThani Rajabhat University, UdonThani, Thailand, in 2005, and diploma degree in teaching profession from Rajabhat Maha Sarakham University, Thailand.

# Dr. Wannapong Triampo

Director and Associate Professor, Institute for Innovative Learning and Department of Physics, Faculty of Science, Mahidol University, Nakhon Pathom, Thailand

# Dr. Narin Nuttavut

Assistant Professor, Department of Physics, Faculty of Science, Mahidol University, Bangkok, Thailand

# Dr. Meechoke Chuedoung

Lecturer, Department of Mathematics, Faculty of Science, Mahidol University, Bangkok, Thailand

# Dr. Darapond Triampo

Assistant Professor, Department of Chemistry, Faculty of Science, Mahidol University, Bangkok, Thailand

# Dr. Charin Modchang

Assistant Professor, Department of Physics, Faculty of Science, Mahidol University, Bangkok, Thailand