The aim of this study was to investigate student-environment fit and perceived need of adjustments for students in the regular upper secondary school, with and without a diagnosis. The students (n = 419) were interviewed with the assessment School Setting Interview. The results showed that for seven of the 16 items, 60% or more of the students experienced that the demands of the school environment were not consistent with their abilities. Girls had a greater need of adjustments in eight of nine SSI school activities. The findings put an emphasis on the importance of recognizing the student's individual's need of adjustments, and on offering flexible support in order to enhance the student-environment-fit and well-being of students in need of special educational support.