摘要：The aim of this research was to examine the effect of GeoGebra-aided REACT
strategy on the understanding of geometry concepts and to investigate the
interaction between learning strategy and spatial ability on the understanding of
geometry concepts. This research involved 60 students of Grade 8 at a private
Junior High School in Borong, province of East Nusa Tenggara, Indonesia. The
quasi-experimental research with control class without pre-test was done. Prior to
the experiment, spatial ability test was conducted to group students into high and
low spatial ability. The research data were obtained from a test consisting of five
questions to measure students’ understanding of geometry concepts. The data were
then analyzed using two-way ANOVA. The results of the research show that 1) the
GeoGebra-aided REACT strategy leads to a higher achievement of the students on
the understanding of geometry concepts if compared to student in conventional
groups (expository), and 2) there was no interaction effect between the learning
strategy and spatial ability on students’ understanding of geometry concepts. The
research recommended that GeoGebra-aided REACT strategy can be used in
mathematics teaching in Junior High School to improve students’ conceptual
understanding of geometry concepts.
