Well, Boko Haram is the main terrorist group. There's a subgroup called Ansaru, and they specialize in targeting westerners. Ansaru has killed Britons, Germans, Italians, people from about 15 different nationalities.
The persecution of children, however, is also done by state governments in the north. If you are a Christian child and you go to a public school, they will try to force you to study Islamic studies, and if you don't, you are punished. I refer to several layers of persecution, and we do have that certainly happening, even in the educational system in northern Nigeria.