The chapter elaborates a case study of one mathematics lesson, via the analysis of the lesson with the help of a model of deep structure of teaching, which divides it into three layers: thematic, conceptual, of competence. The case study is structured using the method of AAA: the teaching is first annotated, then analysed and finally, some alternative actions are suggested.
The analysed lesson was realised in 4th grade which was taught by Hejný's method or in the spirit of genetic constructivism.