Teenagers need around 8 to 10 hours of sleep a night — more than adults — because sleep supports brain development, memory, mood and concentration. Screens can interfere with sleep: the light they emit can delay your body's natural signal to feel sleepy, and engaging content can keep your mind alert when it should be winding down. Good habits — a consistent bedtime, and turning off screens at least 30-60 minutes before bed — support better sleep.
Example
Scrolling on a phone right before bed can make it harder to fall asleep, both because of the screen's light and because the content itself (games, videos) keeps your brain engaged rather than relaxed.
Key terms
Sleep hygiene:
Habits that support good, consistent sleep.
Circadian rhythm:
The body's internal clock that regulates sleep and wake cycles.
Questions
1. Teenagers generally need about how many hours of sleep a night?
4-5 hours
8-10 hours
12-14 hours
1-2 hours
2. Screens right before bed can:
Make it harder to fall asleep
Always improve sleep
Have no effect at all
Replace the need for sleep
3. A consistent bedtime helps:
Support better sleep
Make sleep worse
Have no effect on health
Only matter for adults
4. Sleep supports:
Brain development, memory and mood
Only physical growth, nothing else
Nothing important
Only eyesight
5. It's recommended to turn off screens how long before bed?
At least 30-60 minutes before
Right up until you close your eyes
Never, screens don't matter
5 seconds before
6. A lack of sleep can affect:
Concentration and mood
Nothing at all
Only your hair colour
Only your height
7. Sleep hygiene refers to:
Habits that support good sleep
Washing your hair
A type of screen setting
A school subject
8. Why does screen light affect sleep?
It can delay the body's natural signal to feel sleepy
It has zero effect on the body
It always makes you fall asleep faster
It only affects your eyesight, not sleep
9. The circadian rhythm is:
The body's internal clock for sleep and wake cycles
A type of exercise
A school timetable
A food group
10. Which habit would most likely improve sleep quality?
A consistent bedtime and winding down without screens
Playing video games until midnight
Drinking caffeine right before bed
Napping all day and staying up all night
11. Poor sleep can make it harder to:
Concentrate and manage emotions
Grow taller instantly
Change eye colour
Read faster automatically
12. Why might engaging video content (like an exciting game) before bed disrupt sleep more than reading a calm book?
Exciting content keeps the brain alert rather than relaxed
All screen content has an identical effect
Books have no effect on the brain
Games always help you fall asleep faster
13. A "wind-down" routine before bed might include:
Reading, stretching, or dimming the lights
Intense exercise right at bedtime
Loud music and bright screens
Eating a large meal right before sleeping
14. Why do teenagers often need more sleep than adults?
Their brains and bodies are still developing significantly
Teenagers do not actually need more sleep
It is simply a myth with no basis
Adults need more sleep than teens
15. Why might inconsistent sleep schedules (very different bedtimes each night) be harmful over time?
It disrupts the body's internal clock, making quality sleep harder
Inconsistent schedules have no impact on the body
The body always adjusts instantly with no cost
Only adults are affected by inconsistent schedules
16. Which best explains the link between poor sleep and mood problems in teenagers?
Sleep deprivation affects brain regions involved in emotional regulation
Mood and sleep are completely unrelated
Poor sleep always improves mood
Mood only depends on screen time, not sleep
17. Why might exposure to bright screen light in the evening confuse the body's circadian rhythm?
It can mimic daylight, delaying the release of sleep-related hormones
Screen light has no biological effect
It always improves the circadian rhythm
Circadian rhythms are unrelated to light exposure
18. A student who sleeps 5 hours on school nights and 12 hours on weekends is likely experiencing:
A disrupted sleep pattern that may still leave them tired
An ideal, perfectly healthy sleep pattern
No issues at all with this pattern
Better sleep than someone with a consistent schedule
19. Why is it recommended to avoid caffeine in the afternoon or evening for better sleep?
Caffeine can stay in the body for hours and delay feeling sleepy
Caffeine has no effect on sleep at any time
Caffeine always improves sleep quality
Caffeine only affects adults, not teenagers
20. Which combination of habits would most likely support the healthiest sleep for a teenager?
Consistent bedtime, no screens before bed, and a calm wind-down routine
Variable bedtimes, screens until midnight, and energy drinks before bed
No routine at all, with random sleep times
Screens as the main way to fall asleep every night
21. Feeling irritable and unfocused after a poor night's sleep is best explained by:
Sleep deprivation affecting mood and concentration
A completely unrelated coincidence
Too much sleep the night before
Screen time always improving focus
Answer key (parent copy)
1. 8-10 hours
2. Make it harder to fall asleep
3. Support better sleep
4. Brain development, memory and mood
5. At least 30-60 minutes before
6. Concentration and mood
7. Habits that support good sleep
8. It can delay the body's natural signal to feel sleepy
9. The body's internal clock for sleep and wake cycles
10. A consistent bedtime and winding down without screens
11. Concentrate and manage emotions
12. Exciting content keeps the brain alert rather than relaxed
13. Reading, stretching, or dimming the lights
14. Their brains and bodies are still developing significantly
15. It disrupts the body's internal clock, making quality sleep harder
16. Sleep deprivation affects brain regions involved in emotional regulation
17. It can mimic daylight, delaying the release of sleep-related hormones
18. A disrupted sleep pattern that may still leave them tired
19. Caffeine can stay in the body for hours and delay feeling sleepy
20. Consistent bedtime, no screens before bed, and a calm wind-down routine
21. Sleep deprivation affecting mood and concentration