THEY were gatvol of their maths teacher talking about sex in class instead of teaching them.

So clever pupils from Topaz Secondary School in Lenasia, Joburg started filming him.

Last week, they showed the evidence to their parents, who were furious. One parent said she started worrying when she saw her daughter’s marks for the first and second terms were the same.

“I asked her whether she was struggling with maths or if her teacher was the problem.

“She told me the teacher would only talk about maths for five minutes and then spend the rest of the period talking about sex.

“I didn’t believe her but then she showed me a video.”

Another parent said: “We teach our children not to rush into sex but this man is filling their heads with nonsense. He is sick.

“He tells them that beautiful girls with curves should be used for sex and even demonstrates how they should do it.”

Parents shared videos on a WhatsApp group and on Friday, they met the principal to discuss what had been going on.

Parents said the principal would lodge a complaint with authorities as he didn’t have the power to suspend the teacher.

Gauteng Department of Education spokesman Steve Mabona said: “We are disappointed and strongly condemn the action by the educator. Educators must not cease their responsibility to be guardians and role models. Disciplinary charges will definitely be laid as soon as we verify the necessary information.”