SHENZHEN, Guangdong - Shenzhen is considering extending its nine years of compulsory education to 15 to cover free preschool and senior high school.

The extension would comprise three more years of both preschool and senior high school.

The draft proposal was submitted to the Shenzhen People's Congress Standing Committee for discussion on Wednesday.

Hu Xintian, director of the policy and regulation department of the Shenzhen education bureau, said extended compulsory education would require more government investment, but it was difficult to provide an exact figure now.

Last year, the city's kindergartens enrolled 111,000 children and senior high schools 58,583 students, bureau statistics showed. That means if compulsory education was extended, it would cover an extra 170,000 students each year.

Statistics also show the city's budget for education in 2011 was 9.06 billion yuan ($1.42 billion), accounting for 6 percent of total government expenditure, up 35.4 percent year-on-year.

By the end of last year, the city had 1,705 schools, from preschool institutions to senior high schools, and they enrolled 1.36 million students.

Tian Xiaohong, who manages a factory in Shenzhen's Guangming new district, said his son had just moved from his hometown in Central China's Hunan province and enrolled in a public primary school's sixth grade.

He said that when his son went to a preschool in Hunan, tuition was about 2,000 yuan a year, but there were always other fees.

"If senior high school also becomes free, I would be very happy," Tian said.

An increasing number of cities and counties in China are exploring extending free compulsory education to cover more children.

In August, poverty-stricken Ningshan county in Northwest China's Shaanxi province decided to extend compulsory education to 15 years, also from preschool through senior high school.

In Guangdong's Shipai town, students do not need to pay any tuition from preschool to postgraduate studies, enjoying up to 25 years of free education.

Xiong Bingqi, deputy director of the 21st Century Education Research Institute, a private, non-profit policy research body, lauded the government's efforts.

"Extending compulsory education is a good policy to relieve parents of heavy economic pressure and promote education equality for the whole society," he told China Daily.

The policy was not being introduced around the country because of limited educational resources and concerns among some students who preferred to attend vocational school instead of compulsory senior high school.

"People need free education rather than compulsory education," Xiong said, referring to giving students options in their educational careers.

In China, all citizens must attend school for at least nine years, according to the law.

The government provides free primary school education for six years, starting at age 6 or 7, then three years of junior high school.

Families must pay for preschool and the three years of senior high school if children attend.