If primary schools are the same as junior high schools, they are all from compulsory education publishing houses now.
Not since high school. There are many versions of this kind. There are several editions in Sichuan alone, and the most common one is People's Education Publishing House, referred to as People's Education Edition. I don't know the rest.
Then it belongs to compulsory education publishing house. It's all nine-year compulsory education now.