ABSTRACT
One of the main aims of the present project is to find methods of designing teaching material that stimulates the development of thinking abilities more effectively. In the closing phase of this work, an experiment was carried out in two age groups in regular Hungarian schools to examine the effectiveness of the modified teaching material devised previously. The main principles of this work were that only the contents of the regular teaching material could be used to form structured tasks and exercises and that all the developmental effects should be integrated into the teaching material itself. The developmental activities should not be applied outside the regular framework of the curriculum and extra time should be devoted to the developmental work.
