As a result of young people frequently exposing themselves to loud sounds, researchers are advocating education about the risks of contracting tinnitus. However, how pupils conceive of and learn about the biological aspects of hearing has not been extensively investigated. Consequently, the aim of the present study is to explore pupils' learning about hearing and tinnitus. Pupils in Grades 4, 7, and 8 (aged 10-11, n = 48; aged 12-13, n = 71; aged 13-14, n = 80) were studied. The pupils' learning was evaluated in connection with a teaching intervention based on a teaching-learning sequence (TLS) about sound, hearing, and health. In pre-, post-, and delayed post-tests, pupils were asked to use drawing and writing to express their answer to the question: "What happens to a sound that has reached your ear?" A questionnaire concerning tinnitus, experiences of tinnitus, and listening behaviour was also given. The results show that the pupils' knowledge of hearing and tinnitus had increased as a result of the intervention and that this knowledge was well retained one year later. The pupils in Grade 4 learned just as much as the older pupils, although it was more difficult for them to understand cell structures and causal chains. To conclude, pupils are capable of learning about hearing and tinnitus already at the age of 10-11. Knowledge of hearing and tinnitus may be an important prerequisite for conceptualizing the risk of being exposed to loud sounds. (Contains 7 tables and 2 figures.)