The modern food system involves high consumption of natural resources and other forms of environmental degradation. This paper is a presentation of internet resources such as scientific contributions, graphics, tables, images, animations and interactive atlases that can help to teach this subject. The discussion contains some subjects considered relevant, found among the cited internet resources, such as a comparison between organic and conventional agriculture. The different amounts of natural resources required for growing different crops, the differences between animal and vegetal food, the food system and strategies to save energy are considered as well. Some documents deal with the consequences of alimentary choices on food security and health. Some texts concern fishery resources, the sustainability of their catch, physical changes of the ecosystems due to overfishing and aquaculture, a fast growing activity which is offsetting the decline of marine fisheries.