Abstract

The aim of this study is to investigate the status of 8th grade students’ recognizing quadrilaterals and understanding hierarchical classification of them when diagonals intersect each other in different situations. The study was carried out by using case study. The sample of this research consisted of twenty four 8th grade students. Data were collected through worksheets which were prepared by the researchers, conversations within the groups and unstructured observations. The results of this study showed that students could recognize the quarilaterals by making some measurements easily but couldn’t see the hierarchical classification of them at desired level.

Key words: Quadrilaterals, hierarchical classification of quadrilaterals.