I spoke with the primary school principal of the school my daughter attended a few years back. The homework she was given each night was keeping her up between 10-11pm. Then she was at the school at 7am for swim practice. Thinking that I was speaking to an educated person (the principal) we discuss the recommended sleep for young children 6,7,8 years old. The principal agreed with me that child psychologists say that 10 hours sleep is necessary for young children. Then when she realized that the amount of homework the school was giving the students each night the child could not come close to meeting the necessary sleep for a growing and healthy young mind and body. She backtracked and told me 8 hours or less. I was not facing an uneducated person I was just facing a liar. So my daughter suffered and often would go to sleep with the books beside her in the bed. Impossible to keep her awake except by terrible measures.
So I fight for the rights of the kids in Hong Kong. When you ask a child in Hong Kong why they do not like school the answer is always “to much homework”. http://www.chinadailyapac.com/article/sleepless-hong-kong