In this study we analysed the familiarity and understanding of 10 environmental concepts amongst Mexican and English school children (aged 7 to 9). The investigation considered the impact of the educational system and the school ethos on the formation of environmental concepts. Results reveal that in general, children of this age have a low to moderate level of environmental literacy. The educational system and pedagogical approach affect the way children learn environmental concepts. Schools with a strong orientation towards the environment seem more capable of helping children with their understanding of environmental concepts. School and television were the major sources of environmental information, but this varied with school ethos. The development of effective environmental policies in schools needs to be considered in order to promote environmental knowledge in the school population. (Contains 3 tables and 3 figures.)