The Role of Ethnomathematics Context in Learning Area of Circle

This article describes the role of ethnomathematics context in learning area of circle by decorating bicycle wheels. Decorating wheels using colored paper needs mathematics, and it is one of the ethnomathematics. Using ethnomathematics as a mathematical context supports students’ understanding of working in the context of the circle area. The research uses Design Research followed by the Gravemeijer model. The phases of this research are developing preliminary design, validating hypothetical learning trajectories in teaching experiments, and evaluating learning design using retrospective analysis. Hypothetical learning trajectories consist of learning purposes, student activities using ethnomathematics context to develop student understanding on circle area, and conjecture of student thoughts. The teaching experiment results show that ethnomathematics’ context contributes to students’ grasp of concepts in a more concrete way, and design contributes to instructional theory on the circle area.