This study was conducted on Idjwi Territory within the southern part of the Island covering Ntambuka Collectivity. It aimed, on the one hand, at studying the rate of schooled girls extending from 2009 to 2014 in primary schools. On the other hand, it sought to determine the declining causes of schooled girls and then to forward a proportion of remedial suggestions in order to increase the number of schoolgirls in that part of the island. On the basis of our genuine investigation, we have come up the following findings: the number of girls decreased systematically as they moved from one class into another. Moreover, the causes of this dwindle of schooled girls are basically due to teachers' immorality, precocious marriages, parents' retrograde culture and poverty, and negligence on behalf of the school girls themselves.