Learning Obstacles of Junior High School Students on the Concept of Triangle

Abstract

Geometry is one of the important topics in school mathematics. Many people solve daily life problems using geometry, including the concept of triangles. However, many students still have obstacles in learning the concept of triangles. This study aims to analyze students’ learning obstacles on the concept of triangle. A qualitative research along with a case study was conducted on 45 students of 9th grade, studying at one of the junior high schools in Majalengka, West Java, Indonesia. The data were collected using triangulation which included document analysis, test, and interview. The results showed that students experienced several types of learning obstacles, including students facing issues in incomplete or inadequate presentation of triangle material (didactical obstacle); their inability to use the triangle concept in the context of non-routine questions (epistemological obstacle); and their inability to follow the learning demands about the definition of triangle, the types of triangles, and the area of triangle (ontogenic obstacle), so that it is indicated that students have problems in understanding the concept of triangle. The results of this study can be used as a reference for developing a more optimal didactical design. Keywords: junior high school, learning obstacles, triangle