In this article, we analyse pre-service language teachers' written plans for demonstration lessons in Germany. Our objective is to reconstruct and quantify generic and subject-specific planning decisions related to adaptive teaching, specified as the ways in which a lesson's main task fits the learning group's cognitive level. The focus is on aspects of generic planning featured in subject specific planning rather than very specific subject planning that reflects the unique aspect of that particular subject discipline. The sample comprises pre-service teachers during induction, surveyed at two time points. The findings show that planning skills can be measured in a reliable way and that subject-specific decisions are more difficult to implement into planning than generic decisions. Skills increase substantially during induction and can be explained by institutional and individual factors using regression analysis. Implications for the design of learning opportunities in teacher education and perspectives for future research are discussed.