The present article presents results obtained from a survey focusing on attitudes to solidarity among upper secondary school students. A relation between positive attitudes to solidarity and future-orientation was evident. The survey results were reinforced by a second study, exploring how students in the Swedish upper secondary school perceived the value solidarity, and whether the future-dimension was reflected in teaching. Twenty-two third-year students attending theoretical and vocational programmes at five upper secondary schools were interviewed. After coding and transcribing, a thematic analysis was performed, categorizing the interview responses into sub-themes, representing different aspects of solidarity and future-orientation. The analysis revealed that these students were not acquainted with solidarity as a concept. In the cases solidarity had been brought up at all in class, the students primarily contemplated it in a historical context. Notwithstanding, several students expressed a definite ambition and readiness to act in a solidary manner in order to contribute to improved social and ecological justice, also in relation to future generations. The interviews furthermore disclosed that teaching rarely had included the future-dimension; the students considered the future to be an individual rather than a shared challenge. In terms of resolving future challenges, such as the climate threat, their confidence in natural scientists and technologists was high, but few students conveyed trust in politicians, or believed that school, teachers, and students would take on an active role. Conclusively, activating the future-dimension in the Education for Sustainable Development (ESD) might be a means to ameliorate the preconditions for youths' environmental moral learning.