NIGERIA, Dec. 4 -- For many Nigerians the classroom once a place of promise and possibility now sits uneasy between two threats the slow rot of a fragile education system and the sudden violence that snatches children from dormitories and assembly halls. In the north, where generations have relied on schools to lift families from poverty, the system is fraying. Tens of millions of children remain out of school. Across states and seasons, stories of abductions and closures have become depressingly familiar, planting a deep public fear about what school attendance now costs.

Nigeria carries a disproportionate share of the world's out-of-school children. UNICEF reports that roughly 10.5 million children aged five to fourteen are not in scho...