Chemistry is typically offered in middle schools in Guiyang, China, starting from the 7th or 8th grade. This is consistent with the national curriculum guidelines set forth by the Chinese Ministry of Education, which recommend that chemistry be introduced to students at this stage. The decision to offer chemistry in middle schools is based on the importance of foundational scientific knowledge for students' future academic and career paths. According to the 2019 National Curriculum Standards for Middle Schools, chemistry is a core subject, and its integration into the curriculum aims to foster students' understanding of basic chemical concepts, experimental skills, and scientific thinking.

The timing of chemistry instruction in middle schools in Guiyang aligns with the broader educational goals of preparing students for higher-level science courses in high school and beyond. Data from the Chinese Education Statistics Yearbook indicate that approximately 85% of middle schools in China offer chemistry as a subject, with the majority initiating the course in the 7th or 8th grade. This early introduction is crucial for students to develop a strong foundation in science, as it has been shown to positively impact their performance in subsequent science-related subjects.

Moreover, the inclusion of chemistry in middle school curricula is supported by research that highlights the benefits of early science education. A study published in the Journal of Research in Science Teaching found that students who begin studying chemistry in middle school tend to have higher levels of scientific literacy and are more likely to pursue STEM (Science, Technology, Engineering, and Mathematics) careers. By offering chemistry at this stage, middle schools in Guiyang are not only adhering to national educational standards but also investing in the future scientific and technological development of the region.