Previous research has shown that interest in and concern about environmental issues tends to decrease in adolescence, but less is known about adolescents' broader consciousness of sustainable development, also including economic and social issues. This study investigates students' sustainability consciousness in the transition to adolescence. This was done by surveying 2,413 Swedish students in the sixth, ninth and twelfth grades using an age-adapted questionnaire. The results unambiguously show that Swedish students' sustainability consciousness dips in adolescence, strongly indicating a need to modify the sustainability education for adolescents. Education for sustainable development is recommended as an approach to meet that need.