This free means that tuition, books and miscellaneous fees are all free. If children are far away from home and want to eat at school, then lunch or dinner expenses need to be paid by themselves. It's not called tuition, is it? The school is not a profit-making organization and can't provide free lunch. Unless there are special subsidies from the state and the government.
I come from Zhejiang. There are many migrant workers in Zhejiang and many people in the class. For example, my son's class, a class of more than 60 people. Considering the safety accidents, I will advise my children to take out accident insurance every year in 80 yuan. This fee is not paid by the school, but by the insurance company. In case of an accident, the insurance company will also pay. This is not tuition, yes, and it is voluntary. Another example is the home-school communication platform provided by the telecommunications department to facilitate communication between school teachers and parents. If you want to attend a semester ranging from 20 to 25 yuan, it's not called tuition, but it's voluntary.
So if you have lunch at home, don't take accident insurance and don't use your mobile phone, then you don't have to pay a penny. I said it was all for my son, but if you ask me how much the tuition is, I will still tell you that it is free. Because I really didn't pay any tuition.
For private schools, depending on the level of the school, the fees to be paid are not necessarily, and some are outrageous. For example, the school where the children of stars attend.
There is also the question of the cost of books. The books provided by the state free of charge basically do not include exercise books of various subjects, such as oral arithmetic training in mathematics, copybooks of new words in Chinese, and papers for exams at ordinary times, all of which are used in class, and children have to pay for themselves. Some schools will contact the local Xinhua Bookstore for the convenience of students, and then Xinhua Bookstore will arrange employees to come to the school to collect fees. It's the same to go to Xinhua Bookstore to buy it yourself.
To sum up, there is no tuition in primary school and junior high school, and it is free.