Is hope concerning climate change related to environmental engagement, or is it rather associated with unrealistic optimism and inactivity? This study on Swedish high school students identified two kinds of hope: constructive hope and hope based on denial. Constructive hope was positively associated with engagement and a perception that teachers respect students' negative emotions concerning societal issues and have a future-oriented, positive, and solution-oriented communication style. Students who felt hope based on denial instead were less inclined to behave pro-environmentally and perceived their teachers as not taking their emotions seriously and as communicating in a pessimistic way. Boys perceived their teachers as less accepting of negative emotions, which explained why they felt more hope based on denial than girls. Practical implications of these findings are discussed.