When the Danish Nursing Education in 2002 became a Bachelor Degree the clinical part of the education was reduced. Therefore, it was necessary to optimize learning in practice. I made a qualitative investigation to describe student nurses' learning processes in non-routine situations where they interact with psychiatric patients. The theoretical framework includes primarily P. Jarvis' concept disjuncture and A. Heller's theory about everyday life. The empirical part of the study is primarily based on qualitative semi-structured interviews with, observations of and obser-views with a volunteer sample of 11 student nurses doing their psychiatric placement in 11 psychiatric wards. The empirical material consists of more than 1.000 transscripted pages. Qualitative content analysis was used. It resulted in further development of Jarvis' concept disjuncture in a concept named collective not-conscious disjuncture, in development of the concept pseudo-everyday life activities and in a categorizing model for and a theory about student nurses' learning processes. The theory includes relations between 4 types of disjuncture, 3 types of content in the learning processes, and factors that provoke transformation from one type of disjuncture to another. Students and mentors are not aware that students are in potential learning situations when they interact on their own with patients, and that it is non-routine for students to act with patients in pseudo-everyday life activities. It may be possible to optimize learning in practice if not-conscious learning possibilities are transformed to conscious learning possibilities.