Hong Kong children have lots of homework and enrichment classes, and sleep time is often sacrificed. But sleep affects learning far more than many parents imagine.
The relationship between sleep and memory
When children are asleep, the brain is not resting — it is organising and consolidating the things learned during the day. Psychologists call this process "memory consolidation". If sleep is insufficient, this process is affected, and what has been learned is more easily forgotten.
What the research tells us
Studies have found that students who get enough sleep generally perform better academically. Moreover, even mild sleep deprivation (for example, one hour less of sleep) noticeably affects concentration and memory.
How much sleep does each age group need?
- Children aged 6-12: 9-12 hours
- Teenagers aged 13-18: 8-10 hours
Many Hong Kong children go to bed at 11 p.m. and have to get up at 6 a.m., sleeping only seven hours — not enough for their age.
How to improve sleep habits
Establishing a fixed bedtime routine is very important. For example, "bathe → change into pyjamas → brush teeth → read a book → sleep". Also, avoid screens for an hour before bedtime, giving the brain time to gradually wind down.