Correctional Services said that “matters are under control” at Johannesburg’s Sun City Prison on Wed.
Parents of pupils at Tholimfundo Primary School in Protea Glen are fed up with empty promises by the Education Department.
The school has been waiting for five years to be extended because of the increasing number of pupils.
In 2002, the school received 14 mobile classes from the department as a temporary measure.
"These classes [mobile] are not conducive for a proper learning environment. We are in the 13th year of democracy but we still have a school like this," said the chairman of the school governing body, Lebogang Klaas.
More than 40 pupils are crammed in each class. The classes have broken windows, doors and cracked floors, which Klaas said are a health hazard. Klaas said if something was not done soon they would march to the department to demand the removal of the mobile classes and for proper classes to be built.
But the department said it was not aware of the situation.
"We will look into the matter when it is brought to our attention," said spokesman Mbela Phetlhe.