A class hour in primary and secondary schools in China is generally 45 minutes.

According to the educational dictionary, class hours refer to the time unit of teaching. A class is called a class hour, and a class hour in colleges and universities is 50 minutes, which is also called "management time". There is usually a 10 minute break between classes. So the teaching time in the morning is 8:00- 12:00, and there are five classes: 1, and the first class is 8:00-8:40.

The second period is from 8: 50 to 9: 30. Section 3: 9:40~ 10:20.

4. Section IV10: 30 ~11:10

5. Section 511:20 ~12: 00.