Why are millions of Nigerian children not in school?

Tens of millions of children in Africa are not in school. In Nigeria, UN data shows that around 18.5 million children are currently out of the classroom. What are the key obstacles, and how can they be resolved? Josey Mahachi talks to Dr. Ibrahim Baba Shatambaya and DW correspondent Shehu Salmanu in Nigeria. DW correspondent Killian Ngala in Cameroon talks to parents and students.