This study investigates the effects of teaching and learning environments on student teachers' approaches to teaching and compares a lecture-based setting to a student-activating teaching environment, in which self-discovery learning by means of authentic tasks is central. Data collection (N = 852) was obtained by a pre-test/post-test design including the Approaches to Teaching Inventory. Though student teachers' approaches changed significantly, the direction is only consistent with the assumption that the student-activating experiences push students towards conceptual change/student-focused approaches; however, not away from information transmission/teacher-focused teaching. In fact, students' approaches to teaching at the start of the experiment are important predictors of their scores after they followed the course on child development under both conditions. Moreover, student teachers' changes in approaches to teaching tend to be affected by variables such as performance, academic self-esteem, perceived workload and students' changes in approaches to learning: variables that operate in distinct ways for diverse categories of approaches and work differently in both settings. In addition, the willingness of students to teach in the way they have been taught is not as straightforward as might be expected. Although several students became convinced of the use of the teaching methods in the experiment for their own practice, the majority of students demonstrate reflective practices, make critical judgements, formulate terms or suggest amendments to the teaching methods before simply adopting them for their own future pupils. (Contains 6 tables and 1 note.)