The science of sleep

Children between the ages of 5 and 11 have specific sleep needs that directly impact their development and daily functioning. According to current research, children in this age range should receive between 9 and 11 hours of sleep each night to support optimal health and development¹. This recommendation is consistently supported by sleep experts and medical organisations, with some suggesting that children aged 6 to 12 years should sleep 9 to 12 hours per 24 hours on a regular basis². These recommendations  are based on extensive research into how sleep affects developing brains and bodies.

For a child who needs to wake up at 7 am for school and requires approximately 10 hours of sleep, this means they should be in bed before 9 pm to ensure they get sufficient rest¹. Sleep patterns naturally evolve as children age, with children approaching the upper end of this age range potentially beginning to experience changes related to puberty that affect their sleep timing, though their need for adequate sleep remains crucial.

Children experience sleep differently than adults, with distinct patterns that reflect their developmental stage. During the first few hours of sleep, children typically experience their deepest sleep of the night, which is particularly important for physical restoration and growth¹. Dreams predominantly occur during the second half of the night, during REM (Rapid Eye Movement) sleep, which plays a vital role in memory consolidation and emotional processing. Some children fall deeply asleep almost immediately when they go to bed, while others may experience a lighter sleep phase for up to 20 minutes, during which they might fidget or mutter before transitioning into deeper sleep¹. This variation is entirely normal and reflects individual differences in sleep architecture.

Children also cycle through different sleep stages throughout the night, with each cycle lasting approximately 90 minutes. Understanding these natural patterns can help parents recognise that some behaviours, such as brief restlessness at certain points in the night, are part of normal sleep physiology rather than concerning sleep problems.

Recent scientific research has revealed the profound impact of sleep on children's developing brains, particularly during the critical primary school years. A groundbreaking study from Boston Children's Hospital demonstrated that inadequate or poor-quality sleep may prevent children's brains from developing strong, efficient neural connections⁷. During early adolescence and the preceding years, brain circuits are rapidly maturing, especially those involved in higher-level thought processes such as decision-making, problem-solving, and executive function⁷. Sleep plays an essential role in facilitating this development through various neurobiological mechanisms. Children who experience frequent night awakenings or poor sleep quality typically display less efficient brain networks, reduced neuroplasticity (the brain's ability to adapt and rewire), and diminished resilience to stressors⁷.

These findings underscore the biological importance of sleep beyond simply feeling rested the next day. The brain undergoes significant maintenance and optimisation during sleep, pruning unnecessary connections while strengthening important pathways that support learning and development.

One particularly concerning finding from recent research is the connection between insufficient sleep and actual brain structure. Studies funded by the National Institutes of Health have found that children who consistently get insufficient sleep show smaller volumes in specific brain regions responsible for critical functions like attention, memory, and inhibition control compared to their well-rested peers³. These structural differences don't merely represent temporary effects but may have lasting implications for cognitive development. The effects of poor sleep appear to continue over time, with differences between well-rested and sleep-deprived children persisting in follow-up assessments two years later³.

While more research is needed to determine whether these changes can be reversed with improved sleep habits, the evidence strongly suggests that prioritising good sleep during childhood is essential for optimal brain development. These findings align with other research showing that sleep plays a crucial role in brain maturation, with inadequate sleep potentially disrupting the delicate processes that establish neural architecture during developmental windows.

Sleep serves as a crucial time for memory processing and consolidation in children's developing brains. During sleep, particularly during specific sleep stages, the brain actively works to sort through the day's experiences, strengthening important connections and discarding unnecessary information⁴. This process is especially active in the period just before waking, when the brain is organising memories from the previous day and preparing for new learning⁴. Without adequate sleep, this essential memory consolidation is compromised, making it notably harder for children to remember basic information like spelling words, math calculations, or instructions for assignments⁴.

The relationship between sleep and memory extends to procedural memory as well, affecting a child's ability to master physical skills such as playing a musical instrument or participating in sports. Sleep researchers have observed that children often demonstrate improved performance on newly learned tasks after a good night's sleep, demonstrating how overnight processing enhances learning beyond what practice alone can achieve.

Children who don't get enough sleep consistently demonstrate trouble concentrating during school and other activities⁴. This diminished attention span directly impacts their ability to absorb new information and participate effectively in classroom learning. When a child cannot maintain focus on what they're trying to learn - whether it's academic content at school or practical skills during extracurricular activities - their educational progress suffers significantly⁴. Teachers frequently report that sleep-deprived children appear distracted, have difficulty following multi-step instructions, and may miss important details during lessons. These attention difficulties often compound over time, as gaps in understanding make subsequent learning more challenging.

Additionally, sleepy children frequently exhibit poorer executive functioning, including reduced ability to plan, organise, and complete tasks efficiently. The classroom implications are substantial, with sleep-deprived children often falling behind academically despite having the cognitive capability to succeed when well-rested.

Perhaps one of the most immediately noticeable effects of insufficient sleep is its impact on children's behaviour and emotional regulation. Children who don't get enough sleep tend to display more challenging behaviours both at school and at home⁴. They often struggle to manage their emotions effectively, resulting in increased irritability, frustration, or emotional outbursts that interfere with social interactions and learning opportunities⁴. Sleep-deprived children may have difficulty cooperating in class, following teachers' instructions, and maintaining positive peer relationships⁴. These behavioural challenges can create a negative cycle where children miss learning opportunities because teachers must focus on addressing behaviour rather than delivering instruction.

Additionally, peers may be less inclined to engage with a child who displays unpredictable or difficult behaviour, potentially reducing valuable social learning experiences. Research has consistently shown that improving sleep quality and duration often leads to significant improvements in behaviour and emotional regulation, highlighting sleep as a fundamental intervention for behavioural concerns.

The sleep environment plays a crucial role in determining how well children sleep. Children's bedrooms should ideally be comfortable, quiet, dark or dimly lit, and cool – with temperatures below 24°C typically considered optimal for sleep⁸. Environmental factors like excessive noise, uncomfortable bedding, or rooms that are too hot can significantly disrupt sleep quality even when children are getting adequate hours in bed.

Additionally, many children are sensitive to certain sensory aspects of their sleep environment, such as clothing textures, light levels, or background sounds. Some children benefit from white noise machines to mask disruptive household or neighbourhood sounds, while others may need blackout curtains to prevent early morning sunlight from causing premature awakening.

The increasing presence of electronic devices in children's bedrooms presents another environmental challenge, as the blue light emitted from screens can suppress melatonin production and delay the onset of sleep. Creating an environment specifically designed to promote rest, rather than stimulation, forms the foundation of good sleep quality.

A child's mental state significantly impacts their ability to fall asleep and stay asleep throughout the night. After a busy day at school, many children find their minds still processing the day's events, worries, or excitement when they should be settling down for sleep¹. This mental activity can lead to difficulty falling asleep, restless sleep, or even nightmares. Children who experience anxiety, stress from academic pressures, or social concerns often have particular difficulty transitioning to sleep.

Additionally, children who have experienced trauma or significant life changes may develop sleep issues as part of their adjustment process. Establishing a calming pre-sleep routine that helps children process their day and transition to a more relaxed state is essential for addressing these psychological barriers to quality sleep. Some children benefit from brief guided relaxation exercises, gentle discussion about any worries, or reassurance about the next day's activities.

Creating psychological safety around bedtime helps signal to the child's brain that it's safe to disconnect from alertness and transition into restorative sleep.

What children consume and how they spend their time in the hours before bed can significantly impact their sleep quality.

Caffeine, which is present in many sodas and some foods like chocolate, can interfere with sleep when consumed within 6-8 hours of bedtime⁸. Even small amounts of caffeine can make it harder for children to fall asleep and reduce sleep quality throughout the night.

Similarly, consuming heavy meals close to bedtime can cause physical discomfort that disrupts sleep, although going to bed hungry can be equally problematic⁸. A light, nutritious snack about 30 minutes before bedtime can help maintain stable blood sugar levels throughout the night without causing digestive discomfort.

Physical activity timing also influences sleep quality, with vigorous exercise too close to bedtime potentially making it harder for children to wind down. However, regular physical activity earlier in the day typically improves sleep quality by helping children expend energy and reduce stress.

Screen time presents perhaps the most significant modern challenge to children's sleep, with research showing that using electronic devices before bed not only delays sleep onset but can also reduce the amount of restorative deep sleep children get throughout the night.

One of the most powerful tools for promoting healthy sleep in primary school children is maintaining a consistent sleep schedule.

Research consistently shows that children sleep better when they have the same bedtime and wake time every day, including weekends and holidays^5|8. When sleep timing varies widely, it disrupts the body's internal clock (circadian rhythm), making it harder for children to fall asleep and wake up when needed.

Staying up late on weekends and then attempting to "catch up" on sleep by sleeping in can actually throw off a child's sleep schedule for several days afterward, creating a pattern similar to jet lag⁵. This disruption often results in difficulty falling asleep on Sunday nights and morning fatigue during the first days of the school week.

Parents can support consistent sleep timing by establishing firm bedtimes based on when children need to wake up, allowing for the recommended 9-11 hours of sleep. While occasional special events may necessitate flexibility, quickly returning to the established schedule helps maintain healthy sleep patterns.

Creating visual schedules or using gentle reminders about approaching bedtime can help children internalise these consistent routines.

A structured, calming bedtime routine serves as an essential transition between daytime activity and nighttime rest.

Children benefit from having a 20-30 minute routine that follows the same sequence every night, signalling to both body and mind that sleep time is approaching^1|8.

Effective routines typically include calm, quiet activities such as reading stories, gentle conversation about the day, listening to soft music, or practicing relaxation techniques. The routine should end in the child's bedroom, helping strengthen the association between that space and sleep⁸.

Consistency in the routine elements matters more than the specific activities chosen, though avoiding stimulating content is important. Bedtime routines work by leveraging the power of behavioural conditioning, with the repeated sequence of activities serving as cues that prepare the brain and body for sleep. Over time, simply beginning the familiar routine triggers physiological changes such as increased melatonin production and decreased alertness.

For children who resist bedtime, having a clear, predictable routine can reduce anxiety and arguments, as expectations become established and non-negotiable parts of the daily schedule.

In today's digital world, managing technology use has become a critical component of healthy sleep habits for children. Screen-based devices emit blue light that can suppress melatonin production and delay the onset of sleep⁵.

Additionally, the engaging and often stimulating content on these devices activates the brain rather than preparing it for rest.

Experts recommend avoiding all screen time for at least one hour before bedtime and keeping televisions, computers, tablets, and phones out of children's bedrooms entirely⁵. This technology-free buffer zone before sleep allows the brain to naturally transition into sleep-ready states. Parents can replace evening screen time with alternatives like reading physical books, listening to audio stories, or engaging in quiet family conversations. For families where complete technology removal proves challenging, utilising night mode settings that reduce blue light emissions can help minimise impact, though completely avoiding screens remains the ideal approach. Establishing family-wide technology practices, such as charging all devices overnight in a common area rather than bedrooms, supports not only children's sleep but often improves parents' sleep quality as well.

Creating the optimal physical environment for sleep significantly influences how well children rest throughout the night. A child's bedroom should be comfortable, quiet, and maintained at a cool temperature below 24°C⁸.

While complete darkness promotes the best sleep for most children, many benefit from having a small night light to alleviate fears of the dark⁸.

The sleeping surface itself matters considerably, with appropriate mattress support and comfortable, breathable bedding contributing to uninterrupted sleep. Some children have specific sensory preferences regarding bedding textures or pyjama materials that, when accommodated, can improve sleep quality.

Many children also find security and comfort in having a special stuffed animal or soft blanket that provides emotional reassurance when parents aren't present⁵. These "transitional objects" help children feel safe and can ease the transition to independent sleep.

Parents should ensure the bedroom is associated exclusively with positive experiences, avoiding using it as a location for time-outs or other punishments⁸. When children view their bedroom as a safe, pleasant space rather than one connected to negative experiences, they're more likely to settle into sleep without resistance or anxiety.

While many parents focus on bedtime challenges, nighttime awakenings represent another significant sleep disruption for many primary school children.

Research indicates that nighttime awakenings are quite common, with prevalence varying by age⁶. These awakenings can significantly impact overall sleep quality and daytime functioning when frequent or prolonged.

When children wake during the night, parental responses should be brief and minimally stimulating, reinforcing the expectation that nighttime is for sleeping⁵. Parents should avoid turning on bright lights, engaging in extended conversations, or allowing children to engage with screens during these awakenings.

For children who regularly wake during the night, implementing a consistent response protocol helps establish expectations and reduces the reinforcement of waking behaviours. Teaching children self-soothing strategies they can employ independently when they wake, such as deep breathing or mentally reciting a favourite story, empowers them to return to sleep without parental intervention. Some children benefit from having a dim nightlight or keeping a small cup of water beside the bed to address basic needs without requiring parental assistance.

Importantly, frequent nighttime awakenings (three or more times per night) in school-aged children may warrant discussion with healthcare providers, as they can indicate underlying sleep disorders, anxiety issues, or other health concerns requiring attention.

Many primary school children experience periods of bedtime resistance or anxiety that can significantly disrupt sleep onset.

This resistance often stems from separation anxiety, fear of missing out on family activities, worry about the next day, or generalised anxiety that becomes more pronounced in the quiet of bedtime¹.

Addressing these concerns requires a balanced approach that acknowledges feelings while maintaining consistent sleep expectations. Creating opportunities earlier in the evening for children to express worries and receive reassurance can prevent bedtime from becoming the primary time for processing anxieties. Some children benefit from having a designated "worry time" well before bed, after which concerns are symbolically put away until morning. For children with fears about separation or safety during sleep, gradual adjustment strategies might include parents initially sitting near the bed and gradually moving further away over successive nights as the child's comfort increases.

Bedtime resistance can also stem from children testing boundaries, necessitating clear, consistent limits around sleep expectations. Positive reinforcement systems that acknowledge and reward cooperative bedtime behaviour can be effective for many children, though the primary focus should remain on helping children develop intrinsic motivation for healthy sleep habits rather than relying solely on external rewards.

While occasional sleep difficulties are normal, persistent sleep problems warrant professional attention. Parents should consider consulting healthcare providers when sleep issues significantly impact a child's daytime functioning, mood, or academic performance over an extended period³.

Signs that may indicate the need for professional evaluation include chronic difficulty falling asleep (taking more than 30 minutes most nights), frequent nighttime awakenings that the child cannot resolve independently, excessive daytime sleepiness despite adequate time in bed, snoring accompanied by gasping or pauses in breathing, persistent nightmares, or unusual behaviours during sleep such as sleepwalking or night terrors.

Healthcare providers can help determine whether sleep difficulties stem from behavioural factors, anxiety disorders, neurodevelopmental conditions, or physical sleep disorders such as sleep apnoea or restless legs syndrome. Treatment approaches vary based on the underlying cause, potentially including behavioural interventions, environmental modifications, or in some cases, medical treatments.

Many families benefit from working with professionals who specialise in paediatric sleep, such as sleep psychologists or certified sleep consultants, who can provide targeted strategies for a child's specific sleep challenges. Maintaining a sleep diary documenting bedtimes, wake times, and nighttime disturbances before the appointment can provide valuable information to healthcare providers evaluating sleep concerns⁵.

Establishing a supportive pre-sleep routine helps children transition from the stimulation of daytime activities to the calm state conducive to falling asleep.

Effective pre-sleep routines typically begin 30-45 minutes before the designated bedtime and gradually decrease stimulation levels^1|8. Parents might begin with slightly active components like cleaning up toys or taking a warm bath, then transition to increasingly calming activities such as putting on pyjamas, brushing teeth, and reading quiet stories. Consistency in both the sequence and timing of these activities helps strengthen their effectiveness as sleep cues.

Many children benefit from incorporating brief mindfulness or relaxation exercises into their routine, such as taking several deep breaths or practicing progressive muscle relaxation. For children who struggle with racing thoughts at bedtime, a brief period of "worry time" earlier in the evening allows for addressing concerns before the sleep routine begins.

Parents can further enhance the routine by gradually dimming household lights and reducing overall stimulation levels throughout the house as bedtime approaches. This environmental shift supports the natural increase in melatonin production that facilitates sleep onset.

How parents communicate about sleep significantly influences children's attitudes toward it.

Rather than framing sleep as a punishment or unwelcome interruption to fun activities, parents can discuss sleep as an essential tool for growth, learning, and feeling good^3|4. Age-appropriate explanations about how sleep helps the brain grow stronger, supports learning new skills, and helps regulate emotions can help children understand sleep's value. Parents might explain that sleep works like a "battery charger" for the brain or compare it to how plants need darkness as well as light to grow properly.

Celebrating improvements in sleep habits with specific praise helps reinforce positive behaviours: "I noticed you followed our bedtime routine without reminders tonight, and your body got the rest it needed to be ready for your math test."

Older primary school children often benefit from understanding the science behind sleep in simplified terms, such as learning about how memories are strengthened during sleep or how the brain cleans itself while they rest. This knowledge-based approach helps children develop intrinsic motivation for good sleep habits rather than simply complying with parental rules.

Children's sleep habits don't exist in isolation but are influenced by the broader family context and parental attitudes toward sleep.

When parents demonstrate that they prioritise sleep in their own lives, children are more likely to value healthy sleep habits⁸. Families can implement "wind-down time" for everyone in the household, during which screens are turned off and quieter activities prevail in the hour before children's bedtimes. This not only helps children transition to sleep but prevents them from feeling they're missing exciting family activities.

Parents can model healthy sleep attitudes by discussing their own sleep needs and the steps they take to ensure good rest. Family schedules should be designed with sleep needs in mind, sometimes necessitating difficult decisions about limiting evening activities or adjusting morning commitments to protect adequate sleep time.

Weekend and holiday planning should include strategies for maintaining relatively consistent sleep timing while accommodating special events. When the entire family views sleep as a non-negotiable foundation for health and wellbeing rather than an inconvenience or luxury, children are more likely to internalise healthy sleep attitudes that serve them throughout life.

Fostering independent sleep skills represents one of the most valuable gifts parents can give children, benefiting them not only during the primary school years but throughout life.

Teaching children to fall asleep independently involves putting them to bed when they're drowsy but still awake, allowing them to experience the transition to sleep in their own beds⁵. This practice helps children associate their bed with the process of falling asleep rather than expecting to fall asleep elsewhere and be transferred to bed. Parents can support the development of these skills by gradually reducing their involvement in the falling-asleep process, perhaps moving from lying with a child to sitting nearby, then sitting further away, and eventually just checking in briefly.

Children benefit from having specific strategies they can use independently when they have trouble falling asleep or wake during the night, such as deep breathing, positive imagery, or focusing on relaxing different parts of their body. Parents might introduce the concept of "sleep helpers" such as a special stuffed animal or soft blanket that provides comfort during the night⁵.

Celebrating milestones in sleep independence reinforces progress without creating pressure, with comments like "I noticed you fell back asleep on your own when you woke up last night – your brain is getting really good at knowing how to rest when it needs to."

1. https://raisingchildren.net.au/pre-teens/healthy-lifestyle/sleep/school-age-sleep
2. https://aasm.org/resources/pdf/pediatricsleepdurationconsensus.pdf
3. https://newsinhealth.nih.gov/2022/10/kids-sleep-linked-brain-health
4. https://raisingchildren.net.au/toddlers/sleep/understanding-sleep/sleep-learning
5. https://choc.org/wp-content/uploads/2016/04/Sleep-Hygiene-Children-Handout.pdf
6. https://jcsm.aasm.org/doi/10.5664/jcsm.7164
7. https://answers.childrenshospital.org/sleep-brain/
8. https://www.nationwidechildrens.org/specialties/sleep-disorder-center/sleep-tips-for-children
9. https://www.childrens.health.qld.gov.au/health-a-to-z/healthy-sleep
10. https://www.healthdirect.gov.au/sleep-tips-for-children
11. https://www.nih.gov/news-events/nih-research-matters/children-s-sleep-linked-brain-development
12. https://karger.com/anm/article/75/Suppl.%201/44/42656/Sleep-and-Early-Brain-Development
13. https://pmc.ncbi.nlm.nih.gov/articles/PMC7442661/
14. https://www.sleephealthfoundation.org.au/sleep-topics/sleep-tips-for-children
15. https://kidshealth.org/en/parents/sleep.html
16. https://www.health.gov.au/sites/default/files/documents/2021/05/24-hour-movement-guidelines-birth-to-5-years-brochure.pdf
17. https://theconversation.com/late-bedtimes-and-not-enough-sleep-can-harm-developing-brains-and-poorer-kids-are-more-at-risk-230933
18. https://www.sleepfoundation.org/children-and-sleep/sleep-and-school-performance
19. https://kidshealth.org/en/parents/sleep-hygiene.html
20. https://health.choc.org/handout/age-by-age-sleep-tips-for-kids-and-teens/
21. https://www.schn.health.nsw.gov.au/kids-health-hub/healthy-sleep-children/sleep-patterns-and-behaviour-children
22. https://www.sleepfoundation.org/children-and-sleep
23. https://www.mcri.edu.au/impact/a-z-child-adolescent-health/s/sleep
24. https://www.sleepfoundation.org/children-and-sleep/sleep-strategies-kids
25. https://acamh.onlinelibrary.wiley.com/doi/10.1111/jcpp.12296
26. https://pmc.ncbi.nlm.nih.gov/articles/PMC1978403/
27. https://pmc.ncbi.nlm.nih.gov/articles/PMC4180085/