The notice of the Education Bureau puts forward seven measures, which can be summarized as "paying attention to, ensuring time, preventing interference and improving quality". In terms of "guarantee time", the notice puts forward three "important times". One is the necessary sleep time, which should reach 10 hour for primary school students, 9 hours for junior high school students and 8 hours for senior high school students. The other is the school schedule. Pupils usually attend classes no earlier than 8: 20 in the morning and middle schools no earlier than 8: 00. At the same time, it is stressed that schools are not allowed to require students to arrive at school in advance, which is conditional. 3. Bedtime at night is generally no later than 2 1: 20 for primary school students, 22: 00 for junior high school students and 23: 00 for senior high school students. In terms of "anti-interference", the notice requires that homework, off-campus training and games should make way for students to sleep. Primary school students basically complete written homework in school, and middle school students complete most written homework in school. Off-campus offline training should end no later than 20: 30, and online live training should end no later than 2 1: 00. In addition, you need to ensure that you are not a minor from 22: 00 to 8: 00 the next day.