The gender gap in education against females becomes smaller as the level of development increases and turns in their favor in developed countries. Through analysis of regional variation in the gender gap within Turkey,which displays a similar pattern to the cross-country pattern, this paper studies the factors that lead to the emergence of a gender gap against females. The data for student achievement and aspirations for further education during compulsory school show that females are just as well prepared and motivated for further education as their male counterpartsacross regions with very different levels of development. Despite this fact, large gaps arise in high school registration and completion in less developed regions, but not in developed ones. We find that larger sibship size is the main driver of gender gaps in less developed regions. While social norms have a negative influence on female education beyond compulsory school, they play a relatively small role in the emergence of gender gaps. Theseresultsare consistent with the fact that resource-constrained families give priority to males for further education, leading to the emergence of education gender gaps.