Realistic mathematics education in initial geometry teaching

The aim of this paper is to examine in which way teaching approach Realistic Mathematics Education in initial geometry teaching influences students' achievements (according to the levels of knowledge) and reasoning, as well as students' motivation for learning. We have used experimental method here. We have studied geometry bases and didactical-methodological bases of geometry as well as theoretical foundation of the teaching approach Realistic Mathematics Education using the method of theoretical analysis. Innovative textbook, which is supporting Realistic Mathematics Education approach, models and actions we have tried to make teaching more efficient and improve levels of students' achievements. Introducing Realistic Mathematics Education and additional innovative mathematics textbook positively influences achievements and students motivation of the 4th grade in geometry and this approves effect of the chosen teaching approach. We have also presented innovative mathematics textbook as practical implication which supports constructivists' approach to teaching in Realistic Mathematics Education and we pointed at key results and their methodological implications on mathematics teaching, obtained by experimental research. Our opinion is that the programme in a long lasting approach would show greater effect and we posed questions for further research in teaching geometry, which is more directed to development of research in measuring length, area and volume, especially in initial teaching.