Abstract
Mathematical disposition is a student's tendency to view mathematics as something reasonable, useful, and worth pursuing, thus contributing to success in learning mathematics at the junior high school level. This study aims to determine the effect of an ethnomathematics approach integrated into conventional learning on the mathematical disposition of seventh-grade students at MTsN 1 Padangsidimpuan City, by controlling for the students' initial mathematical disposition abilities. The study used a quasi-experimental method with a nonequivalent control group design, involving an experimental class receiving conventional learning containing ethnomathematics of Mandailing culture and a control class receiving conventional learning without local cultural content. Data were collected using a Likert-style mathematical disposition scale at the pretest and posttest stages, then analyzed using a one-way Analysis of Covariance (ANCOVA) with pretest scores as a covariate. The analysis results showed that after statistically controlling for initial mathematical disposition abilities, the average mathematical disposition of the experimental class remained significantly superior to that of the control class, with the covariate of initial ability also contributing significantly.
