This thatched roof hut is one of several structures that comprises a Himba homestead. The others being for work, storage and corralling livestock. The walls are made using a sort of wattle and daub.
The children mix animal dung with mud using their bare feet to make a sticky material which can be daubed onto the structure forming the walls and floor. In other words, it's a hut made from animal poop and mud.
Home of the Himbas, part of a homestead in Opuwo, Namibia.