\input zb-basic \input zb-matheduc \iteman{ZMATH 2011b.00176} \itemau{Halat, Erdogan} \itemti{Pre-service elementary school and secondary mathematics teachers' van Hiele levels and gender differences.} \itemso{Issues Undergrad. Math. Prep. Sch. Teach., J. 1, Content Knowledge, 11 p. (2008).} \itemab Summary: The aim of this study was to find and compare the pre-service elementary school and secondary mathematic teachers' reasoning stages in geometry. There were a total of 281 pre-service teachers, 125 elementary school teachers and 156 secondary mathematics teachers, involved in the study. The researcher employed a multiple-choice geometry test. This test was developed to find out one's geometric reasoning levels. After the collection of the data, the independent samples $t$-test with $\alpha=.05$ was used to analyze the data. The study found that there was no statistically significant difference in regard to the reasoning stages between the pre-service elementary school and secondary mathematics teachers, and that although there was a difference with reference to van Hiele levels between male and female pre-service secondary mathematics teachers favoring males, there was no sex-related difference found between male and female pre-service elementary school teachers. \itemrv{~} \itemcc{B50 C39} \itemut{van Hiele levels; pre-service mathematics teachers; gender differences; geometry; educational research} \itemli{} \end