A 17-year-old male student lost control after receiving an 18 out of 20 on a maths test at a private school in Uthai Thani, Thailand, on August 5.

He approached his teacher to ask why he didn’t get a perfect score. She explained that although his answers were correct, he did not show his working, so he could not receive full marks.

The teacher suggested he check with other teachers about her marking method. After asking around, he learned that her method was correct.

The student came back to the classroom and demanded that his teacher increase his grade, even though he knew she was right. When she refused, he became angry, kicked a desk, and left.

About ten minutes later, he returned, demanding that the teacher apologize. When she asked who should apologize, he became furious.

The teenager then launched a violent attack, striking the teacher repeatedly in the head. She tried to push him away and move to safety, but he charged again and delivered a front kick.

In total, the student hit the teacher 17 times in front of 20 students. She was rushed to the hospital with broken ribs, a bruised eye, and swelling on her head.

The teacher filed a police report and is expected to give her statement. The student has been removed from the school, and his parents contacted the teacher to apologize.