In many countries young people have to pass quite marked transitions from one school form to another during the time of their puberty. What do these transitions mean from a student perspective? An interesting example is how these matters have been handled in Sweden. Since the last school reform, the school levels are officially abandoned. This must be interpreted as if a school without marked transitions between different school levels is for the better. Supported by the new reform, today many smaller schools keep their students all nine years, resulting in smoother or invisible transitions. Traditionally in the comprehensive school of Sweden (age 7-16), there had been a marked transition to the senior level at the age of 13, often implying the transfer to a new school with new schoolmates and subject teachers. In practice, the new and the old system still exist in parallel. An important question is, whether the changes made are in the interest of the young people involved. Accordingly, the aim of this paper is trying to deepen our understanding of, what marked transitions from one school level to another mean from the perspective of young people. In a longitudinal ethnographic case study, an interpretive approach, with a relational interpretation perspective, is chosen in order to get hold of the young peoples' meaning perspectives, not limiting the analysis to what is explicitly but also implicitly expressed.. In this paper, data from life history interviews with 62 students from two senior level school classes, gathered at three occasions (age 12-21), are scrutinized. The young people interviewed belong to the last generation of comprehensive school students, where almost everyone went through marked transitions to their senior level. The interviewees express how the transition to their senior level school might be regarded as something they had to go through. Even if it had functioned as a critical incident for many of them, the transition had been something no one wanted to have missed. It was like a natural crises in the time of their puberty, a crises everyone has to pass, something important in their personal development. The transition to the senior level school might be recognized as an institutionalized border between childhood and adolescence. Applying the concept rites of passage, these transitions might be interpreted as an initiation rite to adolescence in our modern society. Once confirmation in Swedish church played a crucial role in this respect. Until now, in Sweden, the transition to the senior level school seems to have played a similar role. However, if young people of today are in favour of these marked transitions on the threshold to adolescence, how can we explain what is happening in the Swedish school system of today? Keywords: adolescence, childhood, life crises, rites of passage, student perspective, transitions in school