In this paper we aim to demonstrate that a new ecological norm has emerged and is becoming essential. Two studies using the self-presentation paradigm examined student's adherence to and knowledge of this pro-ecological norm. In Study 1 (France and Great Britain, N = 199), normative adherence and social valorization scores were estimated. Participants' answers were oriented towards more ecologically favorable attitudes and behavior when asked to give a positive image of themselves (social valorization), than answers given under standard conditions (normative adherence). Also, women were found to be more pro-environmental than men. Study 2 (France, N = 182), replicated the results of Study 1 and further examined knowledge of the social norm using the concept of normative clear-sightedness. Results show high scores of normative clear-sightedness concerning the ecological norm, reflected in a capacity of manipulating self-presentation by giving more or less pro-environmental answers. We conclude that not only adherence to but also knowledge of an ecological norm, indicating what is appropriate to think and to do regarding the environment, have been identified here, and discuss the observed gender differences.