One aim of environmental education is to persuade people to act in more proenvironmental ways. However, there is not a linear relationship between environmental knowledge in general and a willingness to act pro-environmentally. This research explores, using a specially-devised questionnaire, Turkish school students’ beliefs about the benefits of specific actions for reducing global warming (their Believed Usefulness of Action), their readiness to adopt them (their Degree of Willingness to Act), and the relationships between these. Students appear willing to take certain actions such as switching off un-used electrical items, but unwilling to undertake other actions such as increasing their use of public transport. Planting more trees was thought to be the most useful action, whereas few students appreciated the role that buying fewer new consumables might play. A novel index, the Potential Effectiveness of Education, was constructed to quantify the relationships between these two parameters for specific actions. For some actions, such as purchasing fewer new goods, there were stronger relationships between a belief in the effectiveness of an action in reducing global warming and the willingness to undertake it. Teaching about the benefits of such actions might be effective in terms of encouraging individuals to adopt them.