Aim: The mental health of teachers is the present focus of research into teaching. Investigations show that early retirement is characteristic of the teaching profession. At least one in every three teachers retires prematurely. Often work-related mental illnesses are the reason. In particular, teachers at technical colleges suffer more often from psychic strain than do teachers at other types of schools. In this context, the confrontation with difficult pupils is seen as especially burdensome. The aim of the pilot study was to record objectively teacher-pupil interactions and to evaluate this interaction from both the perspective of the teacher and, more especially, that of the pupil. Our intention was to produce recommendations for successful teacher-pupil interaction and thus a pre-emptive contribution towards long-term teaching that avoids overstraining the pupils. Method: Following the “RHIA-Unterricht” procedure, we conducted observations of teacher-pupil interaction in 30 lessons at two technical colleges. In addition, teachers (n = 13) and pupils (n = 433) were asked about their views of teacher-pupil interaction, about problems and expectations. Results: The high proportion of lessons disturbed by pupils, which has been observed independently of subject or course of study, is indicative of significant objective strain for teachers. The teachers’ competence in handling critical situations needs to be improved. At the same time, pupils look for more appreciation from the teacher as well as for a mixture of assertiveness and socially integrative behaviour to improve teacher-pupil interaction. Discussion and Conclusion: These results reveal a necessity for changes in teaching to avoid strain on the teacher and to improve the interaction between pupils and teachers; conflict management training programmes for student teachers and technical college teachers are being tested at present. Furthermore, courses for technical college pupils in decision-making and responsibility are currently being developed.