She will arrive at the school on Monday accompanied by her lawyer. The provincial education department has promised a "full-scale investigation".
The boys face charges that include breaching provisions of the SA Schools Act. They might also have breached school policies. One of the T-shirts had the following words inscribed on it: "EFF our last hope of getting our land back."
The boys will face a hearing on October 21.
"When I asked my son why he did it, he said for the fun of it," said the mother. "He had never been exposed to what to write or not to write. They didn't see anything wrong."
She said she told her 17-year-old son to concentrate on his studies.
"I told him that his family and the nation love him. We as adults will sort it. What they did was at their own peril. We are not politically affiliated so this came as a surprise to me. We are not fighting with Maritzburg College. We just want them to drop the charges. He cannot be subjected to a disciplinary hearing two days before he writes his final exams."
The Maritzburg College governing body, through lawyer Jaco van der Merwe, confirmed the disciplinary action.
"On the face of it, the picture and the circumstances under which it was taken and published, appear to contravene provisions of the SA Schools Act, certain regulations promulgated in terms thereof and the school's own code of conduct for learners and [its] social media policy.