... study area. Four schools at the Si Chomphu district, KhonKaen Province; namely the Si Chomphu Kindergarten, Ban Mai Sok Som Kob, Ban Nong Ta Kai and Choom Chon Ban Wang Perm School participated ... the directors and teachers of 4 government schools; Choomchon Ban Wang Perm, Nong Ta Kai Pittaya, Ban Mai Sok Som Kob, and Si Chomphu Kindergarten school, Khon Kaen province, Thailand. The study ... team. The selection of schools was based on a simple random sampling technique from schools with not less than 120 and not more than 1,500 school children. From the selected schools, out of 1.158...