The ability to analyses critically is a skill that one develops during academic education, and which is thus also of importance in professions based on academic qualifications. The aim of the study was to investigate how continuous guidance and tutoring during student teachers' period of in-school teaching practice can challenge and assist the student's competence at critical analysis. Over a twelve-month period, six student teachers kept a digital logbook and produced video documentation of their classroom work while on placement. The material was followed and mentored on an ongoing basis by the students' lecturers at the university. The logbook and the feedback from tutors form the empirical data for the study, and thus the documentary foundation for a consideration of what the practical application of critical analysis in teaching contexts looks like. The study shows that regular documentation, together with a mentoring process rich in feedback, create conditions which enable the student to develop a more analytical approach. The study also shows how tutor's mentoring balances different kinds of feedback: encouragement, the highlighting of broader possibilities, challenging, and discussion. The student poses new questions, concerning subjects such as the value of the logbook in comparison with other forms of documentation, or different possible models for tutoring and mentoring during periods of practical teaching experience.