The purpose of this research is to investigate students' cognitive behaviour in the subjects of function, limit, and derivative according to gender. The research was conducted with the participation of 67 female and 58 male 11th grade students of Gazi High School in Eskisehir in the academic year 2000/2001. The data were obtained through a test consisting of 18 open-ended questions. At the end of the analysis, it was seen that there were significant differences in the steps 'acquiring knowledge of definition', 'understanding', 'analysis', 'synthesis' and 'evaluation of cognitive behaviour' between male and female students, but there were no significant differences in the step 'application of cognitive behaviour'.