... Nguyen Manh Tuan (2009), Van hiele’s viewpoint on forming geometric symbols in kindergatern children and pupils of early primary school, Journal of Education No 224, pp.35-38 Nguyen Manh Tuan ... pp.96-103 Nguyen Manh Tuan (2011), Studying the impact of spatial sense and spatial imagination in upper kindergatern children, Journal of Education No 266, pp.9-11 Nguyen Anh Tuan - Nguyen Manh Tuan ... subjects Nguyen Manh Tuan (2011), The process and a number of methods to form geometric symbols from upper kindergarten to the early primary school children (grades 1, 2, 3), the topic of school INTRODUCTION...