Lack of education is one of the largest obstacles to development. If people do not know what things are harmful to the environment, how can they respect it? Schools play an important role in the formation of positive attitudes towards the environment in young children. In this paper we analyse some possible reasons of in uencing the environmental knowledge and perceptions of English and Mexican school children (aged 7-9). Differences are considered in turn of: the role of national policy, and classroom practice. Children were from eight schools with different environmental ethos. We explore the extent to which culture and the school ethos with regards to the environment have an effect on the formation of environmental knowledge, perceptions and attitudes in young children. A brief description of the most signi cant changes with regards to environmental issues in the educational systems of England and Mexico is presented. The similarities and differences among the two countries are highlighted. Results revealed that schools with strong orientation in environmental studies seem to transmit environmental information more effectively than schools with no environmental policies. The development of effective environmental policies in all schools needs to be considered in order to promote an environmental awareness in the school population.