Are textbooks in high school standardized across the country? _

As of July 2021, the textbooks for high schools are not nationally standardized.

After more than two years of efforts, the compilation and review of the unified teaching materials for the three subjects of ideology and politics, language and history in ordinary high schools have all been completed, and at the beginning of the fall semester of September 2019, they will be first put into use in six provinces (municipalities) such as Beijing and Shanghai, and other provinces and municipalities will be promoted one after another in accordance with the advancement of the new college entrance exams and the actual situation in each province, and the new materials will be used in all of them before 2022.

High school history unified textbook: involving more than 100 historical and cultural celebrities, writings of more than 80

Ordinary high school "history" full set of textbooks **** 5 volumes, of which the mandatory textbook is divided into the "Outline of Chinese and foreign history" up and down 2 volumes, selective mandatory textbooks are divided into the "state system and social governance," "economic and social life," and "cultural exchanges and communication" 3 volumes. Cultural Exchange and Dissemination" in 3 volumes.

The chief editor of the general high school history textbook, the former president of the Chinese Historical Society, a member of the Chinese Academy of Social Sciences, researcher Zhang Haipeng introduced, the textbook presents the history of China's civilization for more than 5,000 years, the content covers the core ideological concepts, traditional virtues and humanism contained in the excellent traditional Chinese culture,*** involving more than 100 historical and cultural celebrities.

More than 80 works on ideology, science and technology, literature and law, more than 50 major inventions and creations such as the four great inventions, astronomical calendars, medicine, mathematics, agronomy, geography, water conservancy engineering, and more than 40 works of art such as painting and calligraphy, music and dance, sculpture, artifacts, etc., guiding the students to form a sense of identity with the Chinese culture and to set up a correct view of culture.

Reference: People's Daily Online - Ministry of Education releases unified textbooks for three high school subjects, to be put into use in the fall semester this year