Abstract: To promote decentralisation and to increase the service efficiency of schools in an area, school maps must be created with the population demographics and distribution in mind. An effective tool that can be used to do this is the Geoinformatic System (GIS). This research’s objectives are to construct proper school maps for the present (2007) situation, using the idealised model according to Hallak and using the p-median model. The area concerned is the Educational Service Area Office-2 in Nakhon Pathom Province in Thailand and the educational levels are primary, lower secondary and upper secondary. After schools maps are constructed from the relevant data using a GIS application, three efficiency assessments are made for each case: Assessments concerning the service area, the schools’ service loading and the students’ average travel distance to the nearest school. The present situation did best to minimise the number of no-service villages owing to the large number of schools. In the case of idealised and p-median models, increasing the travel distance limit that defined the service area boundaries helped reduce the number of no-service villages. The idealised and p-median models increase the school's service loadings while increasing the travel distance due to the small number of school sites generated by the models. However, the p-median model gave shorter travel distances than the idealised model did. After changing the population data by using a linear population growth projection for the years 2015 and 2020, it was found that the school maps generated by the p-median model had little change.