China's college entrance exams, known as gaokao, will start on Thursday, and parents of prospective college students have few ways to help other than keeping their wallets open.

In Beijing, Jiangxi and Fujian, gaokao nannies are in high demand in the job market.

"The nannies must have a college degree and be able to tutor students in their weak subjects. Meanwhile, they should also wash clothes, cook meals and do the housekeeping work," said a manager at the Kongquehe Domestic Service agency, who declined to be named because of interview rules at the company. Domestic service agencies finding gaokao nannies at tutoring companies, luring the tutors away with better pay.

"The average price is 4,000 yuan ($630) for 10 days' work," said the manager, "but right now, you wouldn't have much chance of getting one - our nannies are booked up."

In Beijing, gaokao nannies are paid by the day, 300 yuan on average, according to a Beijing domestic service company named Coleclub.

Workers put up a couplet with blessing words for success in the college entrance examination at a hotel in Nanchong, Sichuan province, on May 28, 2012. [Photo/China Daily]

Besides domestic service agencies, real estate agencies and hotels also have their eyes on the gaokao market.

In Tianjin, almost all houses close to the examination sites are rented, and some were especially sought after as zhuangyuan rooms - rooms that had been rented in past years to someone who scored high in gaokao.

A three-day rental of a zhuangyuan room costs 300 to 800 yuan more than an ordinary room.

"Every year the house rental market heats up ahead of gaokao. A comfortable room can certainly help students get more rest in the break between the morning and afternoon exams, but the zhuangyuan room makes nothing different, except perhaps provide psychological comfort," said Jin Guangze, a teacher at the Experimental High School Attached to Beijing Normal University, a famous high school in Beijing.

According to Shi Qingyun, a doctor at Beijing Shijitan Hospital, some parents even take female examinees to the hospital to take hormone injections that delay their menstruation until after exams.

"Many parents come to ask for the injection, but I wouldn't recommend students take it, because it has side effects, like stomach discomfort, bloating and a bad mood," Shi said.

Examinee Yang Jiaxin has takes no account of such disputed testing aids. "I don't believe in meaningless stunts like the zhuangyuan room or injections. Only my own ability can help me with the exam."

Mo Jinwei contributed to this story.

[email protected]