The objectives of the current study are on the practical use of geoboard in an elementary school class. To do this, we first investigate how come geoboard is significant in a practical use. Second, we present an example of practical use of geoboard connecting with the analysis of the 7th curriculum. Third, we investigate the results of geoboard which is applied to elementary school class. The results of this research are as follows: First, the instruction of using geoboard can give an interest and curiosity to all students. Second, right triangle, rectangle, square and so on can be easily constructed because geoboard is linked by dots. Third, by constructing figures on geoboard and comparing figures which is made by themselves, students could better understand the concept of figures rather than the explanation of teacher. fourth, students can be improved the ability of problem solving and spatial sense by providing experience for exploration. Fifth, students need not to have anxiety for error because geoband is used and so can be corrected easily.