The chapter summarises the results of research presented in previous chapters which concern pupils' difficulties in various areas of mathematics. Namely: pupils' problems when understanding the text (texts in word problems, mathematical texts); pupils' inability to find a mathematical model for a word problem; pupils' difficulties in various areas of mathematics which can be characterised via the transfer from concrete representations to the abstract ones (in word problems, algebraic expressions, measure in geometry); pupils' difficulties with a visual representation of the problem (in the form of drawings, constructions and short records).
The difficulties are described and their probable causes are given.