Computer technology is now available in most schools in Sweden, and in many schools there are special rooms for pupils' work with computers. In preparing for IT, attention is paid mostly to the computers and programs, hardware and software. Little attention is given to the physical conditions of the space. In this paper, the interior design and use of a computer classroom in an upper secondary school are described and the spatial structure was analysed with the method of space syntax. The use of the room was observed during several lessons and a questionnaire about the room, seating preferences and proposals for change, was given to four groups of students. The aim of the study was to evaluate the layout of the classroom with regard to the demands of the teaching situations and the needs of the students. The use of the room differs between lectures but also during one lecture. Therefore, the adequacy of the design must be related to each type of teaching situation. The students show great awareness of the properties of the design. However, the same property can be judged as positive by some and negative by other students. Observed actual seating did not correspond in all details to the seating preferences expressed in the questionnaire. The motives for preferences indicate, that besides functional aspects (such as distance to the whiteboard and the teacher, availability of a computer, location in the back or the front of the classroom, position near door or windows) also social aspects of seating are important to the students. The results show, that it is positive when the design permits flexibility of use and that it would be of interest to let students participate in the planning of the design of the classroom.