Stand no less than half a metre from schoolmates of the opposite sex. No eating watermelons in dormitories. No black stockings allowed for woman teachers. These are just a few of the bizarre school rules found on the mainland that have come under scrutiny, with the strongest criticism for regulations over interaction between the sexes - and in at least one case, between pupils of the same sex. Recent guidelines at Chunhui High School in Wenzhou drew national attention for their warnings against close interaction between classmates of both the opposite sex and the same sex, calling them "severe disciplinary violations". Pupils are prohibited from "maintaining very close relationships", including same-sex relationships, read the guidelines. Rule-breakers could face suspension and may have to return scholarships. At another high school, in Henan province, pupils are banned from lingering in quiet corners, and boys and girls are to mix in groups of five or more. A Hangzhou secondary school has banned boys and girls from appearing on campus as a pair, and they must maintain a distance from each other of at least 50cm. Observers have described these regulations as ridiculous and barbaric, with critics saying the rules about interactions between the sexes are not only unnecessary but may also put pupils on an overly tight leash. An editorial by the China Youth Daily pointed out that school romances could not be suppressed. "It's not right to advocate campus romances, but [schools] shouldn't resort to such extreme measures to control and suppress them." It added that these regulations held back interactions even in normal friendships, which were vital for pupils' personal development. Professor Yang Dongping, an education researcher at the Beijing Institute of Technology, agreed: "I find these school rules very bizarre and beyond my understanding. However, this is not an education phenomenon as it doesn't represent the mainstream. "These school regulations that try to prevent pupils from falling in love are very stupid." Professor Chu Zhaohui, a researcher at the National Institute of Education Sciences, said most of today's school administrators lacked insight into what was appropriate for today's schools because the schools of their days were in the grips of the Cultural Revolution, which ended in 1976. "Most schools then were in a messy state," Chu said.