Protesters gathered at the school on Thursday morning, many of whom are supporters of South Africa’s opposition EFF party according to local media.
Some white parents have removed their children from the school because they fear for their safety.
Provincial education minister Sello Lehare was despatched to the school in the small town of Schweizer-Reneke on a fact-finding mission.
After meeting school staff and education department officials, Mr Lehare confirmed that the form teacher in question had been suspended.
“As government, we would like to condemn any form of racism, alleged or not, and we deeply regret this unfortunate incident taking place in our country 25 years into democracy,” said a spokesperson for the local government leader, Job Lekgoro.
Prof Jonathan Jansen, an expert in education policy and one of South Africa’s most prominent black academics, expressed his disgust on Twitter: