The disputed border region Abyei has received more than 2,600 people fleeing from neighboring Unity State since December, putting pressure on schools.
The head teacher of Comboni Primary School in Agok, Alor Kur, said lessons were very congested and the school had no textbooks.
He said it was impossible for teachers to mark homework for 190 pupils, according to the Abyei Today programme, which is aired on Mayardit FM in neighboring Warrap State.
The head of the Parent-Teachers Association in Comboni school, Martin Monyluak, said the Caritas organisation was relieving the pressure by providing resources for a further eight classes.
The director of primary schools in Abyei, Chol Ngor, said that other NGOs were improving facilities at schools such as Deng Mathiang, Mading Jokthiang, Mabouny, Nyiil, Rumbeek, Awal and Rumamer.
File photo: Women of Abyei (Radio Tamazuj)