Grace knew she was in trouble, but had no idea what she had done wrong.

Last week, a teacher at Bentleigh Secondary College pulled the 16-year-old out of class and took her to a corridor, where her twin sister Tahbisa was waiting.

Grace (right) and her sister Tahbisa (left). Credit:Eddie Jim

The students, who were born in South Sudan, were ordered to take out their braids by the weekend.

"We were told that our hair doesn't represent the school," Grace says. "It was a real shock."