The paper presents a process of optimization of a Content and Language Integrated Learning (CLIL) didactics course for Mathematics teacher-trainees, starting from a traditional face-to-face course through an e-learning project to a blended-learning model. The process of the course design improvement is described; the current model is presented in detail, underlining the advantages of blended approach for CLIL: parallels between effective CLIL didactics and blended learning tools are discussed, methodological approach to course design is explained.
The aim of this case study is to discuss the possibilities of blended learning for CLIL teacher training, offering the students' perspective based on complex feedback survey. The paper aims especially at teacher-training course designers and CLIL practitioners.