Using a geometric computer program achieve learning effects as handling various function and has advantage to overcome the environment of classroom through providing an inquiring surroundings in the figure learning at an elementary school. There are many software for drawing the geometric. But currently most is focus on how to use the softwares without contents. So, It is necessary to develope a geometric software adapted cognitive development of primary schoolchildren. This study is aim to analyze elementary mathematic curriculum based on Van Heiles theory, to develope the software(Geometry for Kids : GeoKids) considering cognitive level of the primary schoolchildren. This software is developed to substitute a ruler and a compass considering cognitive level of the primary schoolchildren. Using mouse, GeoKids software help a child to draw easily lines and circles and this software notice another lines and circle automatically for a more accurate drawing figures. Children can use practically this software in connection with subjects of elementary mathematic curriculum.