Nearly 2.5 per cent of all classes in China are crammed with more than 66 students, while about 10 per cent have at least 56.
By the end of the year, the 86,000 so-called "super-sized" classes with more than 66 students will be "basically eliminated", Education Minister Chen Baosheng said yesterday.
As for "oversized" classes with at least 56 students - there are 368,000 of these - the authorities aim to get rid of them by 2020, he added.
Smaller classes should allow students to better concentrate on their lessons and receive more attention from teachers.
Mr Chen said that overcrowded classes affect the physical and mental health of students as well as the quality of education, and also pose safety concerns.
"This issue is not simply a matter of how many tables to put in a classroom, how many benches, or how you arrange people," he said, adding that his ministry has made "breakthrough progress" in cutting the number of oversized classes by almost 18.3 per cent in the past year.
Mr Chen was speaking on the sidelines of this year's National People's Congress (NPC). He also outlined plans to address the quality of rural education and reduce unnecessary burdens on students.
Improving the quality of education is a pillar of China's plans for "national rejuvenation" and seen as a key to lifting millions of Chinese out of poverty and transforming the nation into a country of innovators - two goals that President Xi Jinping has articulated.
NOT JUST A PHYSICAL PROBLEM
This issue is not simply a matter of how many tables to put in a classroom, how many benches, or how you arrange people.
EDUCATION MINISTER CHEN BAOSHENG, saying that overcrowded classes affect the physical and mental health of students as well as the quality of education, and also pose safety concerns.
Oversized classes are a common problem in urban areas because of a disparity in how education resources are allocated - students flock to schools in cities, causing schools there to expand class sizes.
Besides shrinking class sizes, Mr Chen said it is also necessary to improve the standard of rural boarding schools that children of migrant workers go to.
If done well, this would "stabilise" part of the problem, he said.
He also responded to a question on how the government could lighten the burden of primary and secondary school students, a closely watched topic at this year's NPC session. It was flagged by Premier Li Keqiang last week and in a report jointly issued by four ministries last month.
Apart from reducing pressure from schools, parents and society, Mr Chen said the exam-oriented education system needs to be reformed to reduce the emphasis on academic scores. The government will ban the ranking of students according to test scores, he added.
"The heavy burden on students will gradually reduce," he said.
Education expert Xiong Bingqi, vice-president of 21st Century Education Research Institute, said this was a "systemic issue" in China's education system.
Number of classes with more than 66 students, making up nearly 2.5 per cent of all classes in China.
"People want to get higher marks so they can enter better universities," he said, adding that the solution lies in building a fairer and more equitable education system.