Abstract
Has this happened to you either? You were teaching combinatorics and the students understood everything at first... You were teaching individual combinatorial groups (variations, permutations, combinations) with and without repetition. The students still "got it". But as soon as they had to solve problems where they didn't know which groups they were dealing with, the difficulties started: pupils didn't understand the assignment, they saw different groups behind the problem than the ones behind them, they confused the formulas, etc.
The experiences described above about the misunderstanding of combinatorics and the findings of various researches led us to the need to change the target on which the teaching of combinatorics had been focused so far: the terms "variations", "permutations with repetitions", etc. and combinatorial formulas. On the contrary, we are trying to make the pupils deepen their combinatorial thinking through a series of varied problems with identical mathematical substance.
The author of the paper is also co-author of the textbooks of Prof. M. Hejný et al. for grammar schools. The workshop will include work with a pilot workbook dealing with combinatorics.