Abstract
The main aim of the material is to acquaint the reader with different heuristic (non-algorithmic) solving strategies for word problems. The attention is paid to the importance and role of situations supporting pupils' mathematical creativity (finding individual solving procedures in non-standard situations) and to possibilities that the teacher has for changing pupils' approaches from using a presented algorithm to looking for appropriate, sometimes even "non-scholar" solving strategies.
The importance of a priori analysis of the problem according to the Theory of didactical situation in mathematics is emphasized. The presentation and examples of a priori analyses of selected problems are accompanied by information about possible use of problems in lessons and about original pupils' solutions.
Although the presented teaching unit was conducted in one lesson, it may be divided into several activities and be conducted in a series of lessons.