138 studies · strongest evidence first
- Longitudinal cohort
More screen time at ages 9 and 10 predicted more ADHD symptoms two years later
Strength: Strong2025
Read the summary(opens in a new tab) - Longitudinal cohort
Getting a smartphone by age 12 linked to depression, obesity, and short sleep
Strength: Strong2025
Read the summary(opens in a new tab) - Meta-analysis
Meta-analysis: handwritten notes lead to higher achievement than typed notes
Strength: Strong2024
Read the summary(opens in a new tab) - Policy report
UNESCO: little impartial evidence that ed tech adds value
Strength: Strong2023
Read the summary(opens in a new tab) - Longitudinal cohort
Screen time at age 1 linked to communication and problem-solving delays at 2 and 4
Strength: Strong2023
Read the summary(opens in a new tab) - Policy report
U.S. Surgeon General: not enough evidence that social media is safe for kids
Strength: Strong2023
Read the summary(opens in a new tab) - Quasi-experimental
Natural experiment: Facebook's arrival on college campuses worsened student mental health
Strength: Strong2022
Read the summary(opens in a new tab) - Meta-analysis
Ages 1 to 8: digital picture books lower story comprehension unless very well designed
Strength: Strong2021
Read the summary(opens in a new tab) - Meta-analysis
About 2 to 3% of gamers meet criteria for gaming disorder, more often teens and boys
Strength: Strong2021
Read the summary(opens in a new tab) - Meta-analysis
Meta-analysis: young children learn less from video than from a live person, especially under 3
Strength: Strong2021
Read the summary(opens in a new tab) - Meta-analysis
Meta-analysis: more screen hours, weaker language; co-viewing helps
Strength: Strong2020
Read the summary(opens in a new tab) - Systematic review
Review of rigorous studies: giving students computers alone doesn't improve K-12 learning
Strength: Strong2020
Read the summary(opens in a new tab) - Experiment
Norwegian 10-year-olds scored lower on a reading test taken on screen than on paper
Strength: Strong2020
Read the summary(opens in a new tab) - Longitudinal cohort
More screen time at ages 2 and 3 predicted lower developmental scores later
Strength: Strong2019
Read the summary(opens in a new tab) - Longitudinal cohort
Teens on social media more than 3 hours a day at higher risk for anxiety and depression
Strength: Strong2019
Read the summary(opens in a new tab) - Randomized experiment
Counterpoint: adaptive math software plus small-group teaching boosted learning
Strength: Strong2019
Read the summary(opens in a new tab) - Experiment
Allowing devices in half the lectures lowered exam scores for everyone in the room
Strength: Strong2019
Read the summary(opens in a new tab) - Cross-sectional
Counterpoint: across 355,000 teens, overall technology use explained under 1% of well-being
Strength: Strong2019
Read the summary(opens in a new tab) - Quasi-experimental
Counterpoint: preschoolers who could get Sesame Street in 1969 were more likely to stay on grade level
Strength: Strong2019
Read the summary(opens in a new tab) - Meta-analysis
Reading on paper beats screens for comprehension of informational text
Strength: Strong2018
Read the summary(opens in a new tab) - Meta-analysis
About 1 in 5 young people see unwanted sexual content online, and 1 in 9 are sexually solicited
Strength: Strong2018
Read the summary(opens in a new tab) - Randomized experiment
Randomized trial: allowing laptops in class lowered exam scores
Strength: Strong2017
Read the summary(opens in a new tab) - Randomized experiment
One Laptop per Child in Peru: a laptop for every student, no gain in math or language
Strength: Strong2017
Read the summary(opens in a new tab) - Quasi-experimental
Same course, online instead of in person: lower grades and more dropouts
Strength: Strong2017
Read the summary(opens in a new tab) - Meta-analysis
Teaching handwriting improves students' writing, not just their neatness
Strength: Strong2016
Read the summary(opens in a new tab) - Randomized experiment
Randomized trial: an extra 40 minutes outdoors at school reduced new cases of nearsightedness
Strength: Strong2015
Read the summary(opens in a new tab) - Randomized experiment
Randomized trial: a 'teach your baby to read' program didn't teach babies to read
Strength: Strong2014
Read the summary(opens in a new tab) - Randomized experiment
Randomized trial in California: free home computers had no effect on school outcomes
Strength: Strong2013
Read the summary(opens in a new tab) - Meta-analysis
Meta-analysis of math technology in K-12: modest benefit, near zero in the largest trials
Strength: Strong2013
Read the summary(opens in a new tab) - Quasi-experimental
Home computers in Romania lowered grades in math, English, and Romanian
Strength: Strong2011
Read the summary(opens in a new tab) - Longitudinal cohort
Every minute of screen time at home meant fewer words for toddlers
Strength: Moderate to strong2024
Read the summary(opens in a new tab) - Meta-analysis
Tablets narrow the gap, but print still wins for comprehension
Strength: Moderate to strong2024
Read the summary(opens in a new tab) - Meta-analysis
Leisure reading on devices doesn't build comprehension the way print reading does
Strength: Moderate to strong2023
Read the summary(opens in a new tab) - Meta-analysis
Meta-analysis: educational apps raise narrow skills, with much smaller gains on standardized tests
Strength: Moderate to strong2021
Read the summary(opens in a new tab) - Meta-analysis
Violent video games linked to small increases in physical aggression over time
Strength: Moderate to strong2018
Read the summary(opens in a new tab) - Meta-analysis
Counterpoint: Sesame Street helped preschoolers learn in 15 countries
Strength: Moderate to strong2013
Read the summary(opens in a new tab) - Randomized experiment
Babies learned no more words from a month of a baby DVD than babies who never saw it
Strength: Moderate to strong2010
Read the summary(opens in a new tab) - Policy report
Brookings 2026: for now, generative AI's risks to students outweigh its benefits
Strength: Moderate2026
Read the summary(opens in a new tab) - Meta-analysis
Cyberbullying is associated with later mental-health symptoms
Strength: Moderate2026
Read the summary(opens in a new tab) - Longitudinal cohort
Higher screen time at ages 2 to 4.5 was linked to weaker later language, school skills, and peer relationships
Strength: Moderate2026
Read the summary(opens in a new tab) - Systematic review
The biggest review of under-3s: many risks, many null results, few benefits
Strength: Moderate2025
Read the summary(opens in a new tab) - Systematic review
Review of 46 studies: more screen use, less activity, worse sleep, more attention struggles
Strength: Moderate2025
Read the summary(opens in a new tab) - Cross-sectional
Counterpoint: UK phone bans alone didn't improve teen well-being, but heavy use tracked with lower grades
Strength: Moderate2025
Read the summary(opens in a new tab) - Meta-analysis
Longitudinal review: screen use and socioemotional difficulties predicted each other
Strength: Moderate2025
Read the summary(opens in a new tab) - Meta-analysis
2025 review: more screen time associated with higher odds of myopia
Strength: Moderate2025
Read the summary(opens in a new tab) - Meta-analysis
Global review documents online child sexual exploitation and abuse
Strength: Moderate2025
Read the summary(opens in a new tab) - Lab experiment
Six-month-olds showed distress and physiological arousal during maternal phone use
Strength: Moderate2025
Read the summary(opens in a new tab) - Meta-analysis
Parental technology use was associated with poorer developmental outcomes across the early years
Strength: Moderate2025
Read the summary(opens in a new tab) - Systematic review
For kids specifically, print wins on comprehension; digital wins on engagement
Strength: Moderate2024
Read the summary(opens in a new tab) - Systematic review
Review: heavy screen time before age 2 linked to weaker vocabulary and comprehension
Strength: Moderate2024
Read the summary(opens in a new tab) - Randomized experiment
Tablet and paper distractions both reduced parent-toddler interaction
Strength: Moderate2024
Read the summary(opens in a new tab) - Longitudinal cohort
Screen exposure in the first two years was associated with atypical sensory behaviors around age 3
Strength: Moderate2024
Read the summary(opens in a new tab) - Policy report
PISA 2022: device distraction in math class tracks with lower scores
Strength: Moderate2023
Read the summary(opens in a new tab) - Meta-analysis
Computer-science thinking can begin with activities away from screens
Strength: Moderate2023
Read the summary(opens in a new tab) - Longitudinal cohort
More infant screen time was linked to brain-wave patterns and weaker attention and executive function at age 9
Strength: Moderate2023
Read the summary(opens in a new tab) - Longitudinal cohort
More TV at ages 1 and 2 predicted lower developmental scores a year later, with a two-way link for communication
Strength: Moderate2023
Read the summary(opens in a new tab) - Cross-sectional
Kindergartners with over an hour of daily screens were more developmentally vulnerable
Strength: Moderate2022
Read the summary(opens in a new tab) - Cross-sectional
TV and video games linked to higher odds of overweight, especially in less active teens
Strength: Moderate2022
Read the summary(opens in a new tab) - Longitudinal cohort
Counterpoint: kids who gamed more gained slightly more on intelligence tests
Strength: Moderate2022
Read the summary(opens in a new tab) - Randomized experiment
Phone interruptions reduced shared attention with infants
Strength: Moderate2022
Read the summary(opens in a new tab) - Randomized experiment
Infants’ heart rate and distress rose most when mothers were interrupted by text messages during play
Strength: Moderate2022
Read the summary(opens in a new tab) - Randomized experiment
Phone and paper questionnaires both interrupted mother-toddler interaction
Strength: Moderate2021
Read the summary(opens in a new tab) - Quasi-experimental
Structured keyboarding instruction can build elementary-school skills
Strength: Moderate2021
Read the summary(opens in a new tab) - Systematic review
Screen time and green time pull children's well-being in opposite directions
Strength: Moderate2020
Read the summary(opens in a new tab) - Quasi-experimental
Mooresville, North Carolina: modest math gains after years, and less reading of books
Strength: Moderate2019
Read the summary(opens in a new tab) - Cross-sectional
2019 study: 95% of 135 sampled apps for young children contained advertising
Strength: Moderate2019
Read the summary(opens in a new tab) - Longitudinal cohort
Parents' device interruptions and young children's behavior problems feed each other
Strength: Moderate2018
Read the summary(opens in a new tab) - Cross-sectional
Back-and-forth conversation, more than words heard, tracked with young children's language brain activity
Strength: Moderate2018
Read the summary(opens in a new tab) - Lab experiment
When mothers turned to their phones, babies showed the classic 'still face' distress
Strength: Moderate2018
Read the summary(opens in a new tab) - Lab experiment
When a parent's phone call interrupts, toddlers don't learn the new word
Strength: Moderate2017
Read the summary(opens in a new tab) - Meta-analysis
Meta-analysis of 1:1 laptop programs: small positive effects when well implemented
Strength: Moderate2016
Read the summary(opens in a new tab) - Quasi-experimental
School phone bans in England raised test scores, most for struggling students
Strength: Moderate2016
Read the summary(opens in a new tab) - Meta-analysis
Bedtime device access and use were associated with poorer sleep
Strength: Moderate2016
Read the summary(opens in a new tab) - Lab experiment
Background speech interfered with toddlers learning new words
Strength: Moderate2016
Read the summary(opens in a new tab) - Policy report
OECD: heavy school computer use and big tech investment didn't raise scores
Strength: Moderate2015
Read the summary(opens in a new tab) - Policy report
What makes an app educational: active, engaged, meaningful, and social learning
Strength: Moderate2015
Read the summary(opens in a new tab) - Lab experiment
"The pen is mightier than the keyboard": the original study, and its mixed replications
Strength: Moderate2014
Read the summary(opens in a new tab) - Lab experiment
Toddlers learned new words over video chat, but not from the same video without back-and-forth
Strength: Moderate2014
Read the summary(opens in a new tab) - Lab experiment
Background television reduced the amount and variety of speech addressed to young children
Strength: Moderate2014
Read the summary(opens in a new tab) - Lab experiment
Device multitasking hurts the user and the students who can see the screen
Strength: Moderate2013
Read the summary(opens in a new tab) - Cross-sectional
U.S. children under 2 were exposed to about 5.5 hours of background TV a day
Strength: Moderate2012
Read the summary(opens in a new tab) - Longitudinal cohort
When the TV is on, babies hear fewer words and talk less
Strength: Moderate2009
Read the summary(opens in a new tab) - Lab experiment
Background TV reduced the quantity and quality of parent-child interaction
Strength: Moderate2009
Read the summary(opens in a new tab) - Lab experiment
Background TV cut short toddlers' play, even though they barely looked at it
Strength: Moderate2008
Read the summary(opens in a new tab) - Experiment
Preschoolers who learned letters by hand recognized them better than those who typed
Strength: Moderate2005
Read the summary(opens in a new tab) - Lab experiment
Competing voices made familiar speech harder for young infants to recognize
Strength: Moderate2005
Read the summary(opens in a new tab) - Lab experiment
Infants were distressed when mothers turned to a phone or paper task, with a distinct stress signal for phones
Strength: Preliminary to moderate2025
Read the summary(opens in a new tab) - Randomized experiment
Pilot trial: removing toddler bedtime screens showed preliminary sleep benefits
Strength: Preliminary to moderate2024
Read the summary(opens in a new tab) - Longitudinal cohort
More tablet use at 3.5 was followed by more anger and frustration at 4.5, which then predicted more tablet use
Strength: Preliminary to moderate2024
Read the summary(opens in a new tab) - Longitudinal cohort
Using phones or tablets to calm upset preschoolers was linked to more emotional reactivity months later in boys
Strength: Preliminary to moderate2023
Read the summary(opens in a new tab) - Longitudinal cohort
More TV and DVD time at age 1 was associated with a later autism diagnosis in boys, but not girls
Strength: Preliminary to moderate2022
Read the summary(opens in a new tab) - Cross-sectional
Most apps used by preschoolers contained manipulative design meant to prolong play or prompt purchases
Strength: Preliminary to moderate2022
Read the summary(opens in a new tab) - Experiment
Tablets vs. paper at ages 10 to 13: weaker readers understood less on tablets under time pressure
Strength: Preliminary to moderate2021
Read the summary(opens in a new tab) - Meta-analysis
Smartphone and tablet use linked to higher odds of nearsightedness, but the evidence is mixed
Strength: Preliminary to moderate2021
Read the summary(opens in a new tab) - Longitudinal cohort
More screen time at age 2 predicted weaker executive function gains by age 3 on hands-on tasks
Strength: Preliminary to moderate2020
Read the summary(opens in a new tab) - Longitudinal cohort
TV viewing at 12 months was linked to slightly more autism-like screening symptoms at 2; daily play to fewer
Strength: Preliminary to moderate2020
Read the summary(opens in a new tab) - Lab experiment
Toddlers and parents talk more over print books than tablet books
Strength: Preliminary to moderate2019
Read the summary(opens in a new tab) - Cross-sectional
More handheld device use at 18 months was linked to higher odds of parent-reported expressive speech delay
Strength: Preliminary to moderate2019
Read the summary(opens in a new tab) - Longitudinal cohort
Background TV during infant play was linked to smaller later vocabularies
Strength: Preliminary to moderate2016
Read the summary(opens in a new tab) - Longitudinal cohort
Rising exposure to adult TV from 6 to 18 months was associated with more behavior concerns in toddlers
Strength: Preliminary to moderate2015
Read the summary(opens in a new tab) - Longitudinal cohort
Toddlers later diagnosed with autism or showing ADHD signs had about twice as much screen time at 18 months
Strength: Preliminary2026
Read the summary(opens in a new tab) - Qualitative study
Roblox: children struggle with confusing virtual currency and gambling-like purchases
Strength: Preliminary2025
Read the summary(opens in a new tab) - Cross-sectional
At two months, typical maternal phone use was not associated with observed feeding quality
Strength: Preliminary2025
Read the summary(opens in a new tab) - Lab experiment
Handwriting engages far more of the brain than typing
Strength: Preliminary2024
Read the summary(opens in a new tab) - Experiment
Phone use during breastfeeding interfered with visual responses to infant cues
Strength: Preliminary2022
Read the summary(opens in a new tab) - Cross-sectional
Preschoolers with more screen use had thinner cortex in some visual and language-related brain areas
Strength: Preliminary2022
Read the summary(opens in a new tab) - Cross-sectional
Infants and toddlers with more screen time slept less overall and at night in a Chinese clinic survey
Strength: Preliminary2022
Read the summary(opens in a new tab) - Longitudinal cohort
Longitudinal breastfeeding survey found little link between phone use and later bonding problems
Strength: Preliminary2021
Read the summary(opens in a new tab) - Cross-sectional
More audible phone notifications were linked to more directive parenting and smaller toddler vocabularies
Strength: Preliminary2021
Read the summary(opens in a new tab) - Cross-sectional
Mothers who used more technology around their babies reported weaker attachment and fussier infants
Strength: Preliminary2021
Read the summary(opens in a new tab) - Cross-sectional
Brain scans: more screen use, less developed language pathways in preschoolers
Strength: Preliminary2020
Read the summary(opens in a new tab) - Lab experiment
Fifth graders understood less on screen and didn't realize it
Strength: Preliminary2020
Read the summary(opens in a new tab) - Longitudinal cohort
Combined household media habits predicted poorer attention later in toddlerhood
Strength: Preliminary2020
Read the summary(opens in a new tab) - Lab experiment
Evening light suppresses children's sleep hormone about twice as much as adults'
Strength: Preliminary2014
Read the summary(opens in a new tab) - Qualitative study
Restaurant observations: caregivers absorbed in phones responded less, and sometimes harshly
Strength: Preliminary2014
Read the summary(opens in a new tab) - Lab experiment
Printing letters by hand activates young children's reading circuits; typing doesn't
Strength: Preliminary2012
Read the summary(opens in a new tab) - Randomized experiment
Nine minutes of a fast-paced cartoon briefly lowered 4-year-olds' self-control scores
Strength: Preliminary2011
Read the summary(opens in a new tab) - Policy report
Oregon's school phone order covers personal phones, not school laptops or Chromebooks
Strength: Official source2026
Read the summary(opens in a new tab) - Policy report
AAP 2026: context and time boundaries both matter
Strength: Official source2026
Read the summary(opens in a new tab) - Policy report
U.S. Department of Education, 2026: judge school technology by whether it improves learning
Strength: Official source2026
Read the summary(opens in a new tab) - Policy report
Norway 2026: age-based limits for leisure screen use
Strength: Official source2026
Read the summary(opens in a new tab) - Policy report
England 2026: early-years screen advice replaces an outdated comparison
Strength: Official source2026
Read the summary(opens in a new tab) - Policy report
AAP 2026 technical report: evidence behind the media policy
Strength: Official source2026
Read the summary(opens in a new tab) - Policy report
NCMEC: responding to online sexual threats and exploitation
Strength: Official source2026
Read the summary(opens in a new tab) - Policy report
Oregon's 2024 NAEP results: nearly half of fourth graders below Basic in reading
Strength: Official source2025
Read the summary(opens in a new tab) - Policy report
Sweden returns to printed textbooks and limits digital tools in the early grades
Strength: Official source2024
Read the summary(opens in a new tab) - Policy report
Sweden 2024: no screens under 2, and daily caps by age that don't count schoolwork
Strength: Official source2024
Read the summary(opens in a new tab) - Policy report
France's expert commission: no screens before 3, no phone before 11, no social media before 15
Strength: Official source2024
Read the summary(opens in a new tab) - Policy report
National Academies: population-level causation was not established
Strength: Official source2024
Read the summary(opens in a new tab) - Policy report
Oregon's Early Literacy Success Initiative commits the state to research-aligned reading instruction
Strength: Official source2023
Read the summary(opens in a new tab) - Policy report
American Psychological Association: teen social media needs skills, monitoring, and protected sleep
Strength: Official source2023
Read the summary(opens in a new tab) - Policy report
Canadian Paediatric Society: screen guidance for children under 5
Strength: Official source2022
Read the summary(opens in a new tab) - Policy report
WHO: no sedentary screen time under 2; no more than one hour at ages 2 to 4
Strength: Official source2019
Read the summary(opens in a new tab) - Policy report
Historical counterpoint: RCPCH 2019 declined age-based hour limits; guidance now archived
Strength: Official source2019
Read the summary(opens in a new tab) - Policy report
EEF: choose classroom technology for a clear teaching purpose
Strength: Official source2019
Read the summary(opens in a new tab) - Policy report
Canada's 24-hour guidelines: no more than 2 hours of recreational screen time for ages 5 to 17
Strength: Official source2016
Read the summary(opens in a new tab) - Policy report
AAP 2016: the age-based rules most parents still hear about
Strength: Official source2016
Read the summary(opens in a new tab) - Policy report
Computing as a subject: practical skills, programming, and digital judgment
Strength: Official source2013
Read the summary(opens in a new tab)