When children move from preschool to primary school in Germany, this involves a transition between two distinct systems with regard to political responsibility. Following Rimm-Kaufman and Pianta's (2000) ecological and dynamic model of transition, the research project focuses on the perspectives of parents and professionals on the learning processes of children from socioeconomically disadvantaged families in the transition from preschool to school. Against the backdrop of a socio-constructive conception of learning we examine the microsystemic constructions of parents and professionals with qualitative methods in a longitudinal design. The results presented here draw attention to the 18 months before the child's school entry. It captures the perceptions of parents and educators on the support of the child's learning processes in the family and in the institutional context. Results question the ideal of an educational partnership by emphasising the conflicting demands related to preschool. (author abstract)