In Swedish teacher education, all preschool teacher students have to include a school-based element and to take part in a local educational practice, in a preschool or in another form of educational setting, such as a preschool class or after-school recreation centre. In this study, we have asked a group of supervisors about their perception of the content in learning, knowledge development and supervision and also what is going on in learning and knowledge development situations in practice. The theoretical bases for our analysis are theories of interaction and intersubjectivity. The results show that the content of learning and knowledge development is highly integrated with the situation and practice. A preschool teacher student's learning is understood by the supervisors as something that occurs in interaction, where children and preschool teachers are of great importance. The content of learning is related to practical exercise, observation and reflection together with other preschool teachers. Trying new theories and being curious are also associated with learning.