The situation remains tense in parts of Port Elizabeth's Northern Areas where violence flared up again on Tuesday morning.
But, police say this is not linked to Monday's education protest.
Police spokesperson, Captain Johan Rheeder, says Standford Road is still closed between Gail Road and Windvogel, where most of the trouble is being reported.
He says youths are stoning police vehicles.
He reiterated an earlier appeal to parents to keep their children indoors.
No arrests have been made.