Abstract
The contribution addresses the results of didactic research in the field of conceptual knowledge of pupils and students in geometry, and in spatial ability of pre-service mathematics secondary school teachers. In terms of conceptual knowledge, the geometric misconceptions of 1,458 respondents at lower and upper secondary education, and tertiary education were examined.
The results showed the most frequent students' misconceptions and their persistence at further levels of education. As part of the research on spatial ability, the spatial ability of pre-service mathematics secondary school teachers at the MFF UK, was tested.
The results confirmed the differences in the success rate of women and men, showed a preference for spatial orienta-tion in solving strategies or inconsistent success rate in planar tasks in individual tests. Some partial results of both studies have already been published in journals and proceedings, see the list of references.