Development of Mathematical Learning Devices Using Van Hiele Theory in Geometry of The Students In Grade VIII Secondary High School

摘要

This study was caused by lack of achievement mathematic students' in learning geometry. It can be understood from the observations and the results of daily tests of mathematics students in any of the material geometries in junior high school in Padang. More than 70% students have achievement geometry score less than the passing grade. The way to solve this problem was to develop a learning device by using the theory of Van Hiele. In this study, the learning device has been developed consist of lesson plan and worksheets based Van Hiele theory. The objective of this study was to product mathematics learning device that meet validity, practicality and effectiveness aspect to promote student learning outcomes in geometry. This type of research was the research development using a Plomp model which consists of three phases: a preliminary study, the prototype phase and the assessment phase. The subject of field test in this study were grade VIII students at SMPN 13 Padang in 2015/2016 academic year. Data validity analysis showed that constructivism-oriented math learning device resulting in extremely valid category. Data were analyzed using basic statistics. To find out the difference in geometry learning outcomes between the experimental and control classes used a t-test for a 5% significance level. In data practicality analysis showed that learning device based on Van Hiele teory was practical because it can be applied well in math learning process. Moreover, the level of final result completeness increased up to 78,88%. It means that this device is effective in improving students' achievement of learning geometry. This finding was in line previous study that although many studies all over the world demonstrated that Van Hiele theory can help improve geometric understanding. Based on this study, it recommended that teachers can implement van Hiele's theory in teaching geometry.