Most schools in rural areas had still not received the government's national assessment tests.
Schools across the country were supposed to receive, count and check the necessary papers by Monday.
"As far as we know, most of the rural schools are still waiting for delivery of the tests," SA Teachers' Union (Satu) president Chris Klopper told Beeld.
Satu hoped that all schools would receive the tests on Tuesday, he said.
The annual national assessment tests for pupils in grades one to six were supposed to be delivered to schools on Friday.
The tests, which assess literacy and numeracy, are compiled nationally, but are printed and distributed provincially.
Basic Education Minister Angie Motshekga's spokeswoman Hope Mokgatle told Beeld all tests would be delivered to schools by 9am on Tuesday.