This study aims to examine the high school students' reasons to protect the species, and whether these reasons are affected by grade level and gender. As a result of the study, it was determined that the students attach importance mostly to biospheric reasons. Aesthetic and economic reasons follow them respectively. Although the grade levels and genders of the students did not have an impact on their reasons to preserve the species individually, they were found to have a significant interaction effect. From the findings of the present study, it can be concluded that girls in the 11th and 12th grades attach more importance to biospheric reasons than the girls in the 9th and 10th grades. Moreover, girls in the 11th grade attach more importance to biospheric reasons than do the boys in the 11th grade. No significant difference according to gender and grade level was observed in terms of economic and aesthetic reasons.