This study focuses on mathematics teachers' professional development through elements of Japanese lesson study. The teachers designed a research lesson with regard to sense-making of the derivative using the integration of GeoGebra. In the second year of the four-year lesson study project, seven secondary school teachers--from different Dutch…

Many researchers found that students have difficulties in understanding area measurement. Students mostly focus on applying formula to find the area of certain shapes without knowing what the area is and why the formula works. It is important for the students to know what attribute being measured and to construct the unit for area measurement.…