All schools in Nigeria have been ordered to remain shut until 13 October as part of measures to prevent the spread of the deadly Ebola virus.
The new academic year was due to start on Monday.
But the education minister ordered the closures to allow staff to be trained on how to handle suspected Ebola cases.
Five people have died of Ebola in Nigeria. The West Africa outbreak has centred on Guinea, Liberia and Sierra Leone, killing more than 1,400 people.