Yes. The north faces greater risk academically than the south. The south has always been more advanced, largely because we're on the coast and there was more access to the missionaries when they first came. It was more difficult for the missionaries to go up north, and even the colonial authorities wouldn't let them go far north. So yes, the north is more educationally disadvantaged historically than the south. These practices of not allowing boys to go to school is also a problem, and not allowing girls to go to school is a problem.
I don't have the specific statistics on this, but it's a well-known fact about the disadvantage of the north.