The Size of It
Book 1 total market$0
10-yr earnings, 5 titles$0
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P.H. Dean · the opportunity, sized

It never gets better.
It only gets bigger.

Daily screen time in the United States, by age. Every hour added between four and eighteen was available at four, and no publisher owns the moment parents finally act. That is the ground P.H. Dean is building on: a first title, a catalog behind it, and a market that has never needed the voice more.

Under 2202516
2 to 4202516
5 to 8202516
8 to 12202117
13 to 18202117
The outlined step is the reader. Under 1 hour is the federal recommendation for a six-year-old52 The 8-to-12 and 13-to-18 figures are from 2021 and older than the rest. Common Sense has not published a tween and teen census since.

Parents: the people who buy the book

The worry went from off the list to the top of it in eight years. They see the problem in their own hands too, which is why nothing here can be written as an accusation.

24 child health concerns, ranked Mott Poll, Feb 2025, n = 2,021
Social media
75%
Too much screen time
75%
Internet safety
66%
Unhealthy diet
62%
Child mental health
62%
Smoking, vaping
56%
Bullying
54%
School violence
54%
Guns
51%
Drinking, drugs
47%

Screen issues take all top three of twenty-four1

Where "too much screen time" ranked
2017
Off
Not in the top ten. Bullying led at 61%.3
2023
#1
67% call device overuse a big problem.2
2025
#1
75%, tied with social media.1
What they believe, and what they admit
83%
say kids' mental health is getting worse4
68%
say a child should be 12 or older before owning a smartphone6
65%
say they spend too much time on their own phone43
33%
feel judged by anyone else over it. The pressure is self-generated43

86% set rules. Only 19% keep to them all of the time43

Reading aloud is going away Parents reading often to under-5s
2012
64%
Read aloud frequently to a child under five.9
2024
41%
A 36% fall in twelve years.9
Now
35
US states restricting phones in school. 150,000 UK parents have signed a wait-until-14 pact.1011

Kids 0 to 12: where the habit forms

Daily screen time more than triples between infancy and age eight. The device arrives before the reading does.

Devices arrive early
40%
have their own tablet by age two16
1 in 4
have their own phone by age eight16
+65%
gaming time among 0-to-8s in four years16
1 → 14 min
daily short-form video, ages 0 to 8, 2020 to 202416
Odds of developmental delay 7,097 children, Japan
1 to 2 hours a day
1.61×
2 to 4 hours a day
2.04×
4 or more hours a day
4.78×

Odds of a communication delay at age two, by daily screen time at age one, versus under 1 hour a day. Problem-solving delay runs 2.67× at the same dose. Association, not proven cause.18

What it does to the developing brain Six studies, 2019 to 2023
55%
of the uncinate fasciculus, a tract behind language and executive function, showed lower white-matter integrity in preschoolers with more screen use. The arcuate (16%) and inferior longitudinal (29%) tracts followed. MRI, ages 3 to 5.
Hutton et al., JAMA Pediatrics 2020, n = 4767
8 yrs
later, children who had more screen time at 12 months still showed altered brain-wave patterns and weaker attention and executive function at age 9. Dose-graded from under 1 hour to over 4 hours a day.
Law et al., JAMA Pediatrics 2023, n = 50668
4.78×
the odds of a communication delay at age two for one-year-olds on four or more hours a day, versus under one. Problem-solving delay ran 2.67× at the same dose.
Takahashi et al., JAMA Pediatrics 2023, n = 7,09718
2,441
children followed from two to five. More screen time at 24 months predicted lower developmental scores at 36 months, and more at 36 predicted lower at 60. The reverse direction, weak kids reaching for screens, did not show.
Madigan et al., JAMA Pediatrics 201969
18,905
children across 42 studies: more screen time, weaker language. Two things ran the other way: a parent co-viewing, and an older age at first exposure. Both are what a read-aloud book is.
Madigan et al., JAMA Pediatrics 2020, meta-analysis70
4,277
nine- and ten-year-olds in the ABCD brain-imaging study. Screen media use mapped onto differences in cortical thickness and sulcal depth, and those patterns tracked with lower fluid intelligence and more externalizing behaviour.
Paulus et al., NeuroImage 201971

Six studies, four in JAMA Pediatrics or NeuroImage, that imaged the brain or tracked the same children for years. All are associations; effect sizes are small to moderate and income confounds some of it. It is still the only direction any of them found.

The comfort loop runs both ways
293,000
children under ten, across 117 studies. More screen use predicts later emotional problems, and emotional problems predict more screen use21
0.44
the gaming coefficient, strongest of any medium, against 0.06 for screens overall21
None
of the effect appears in children who stay inside the recommended limits21
Reading for fun is falling in every band

US nine-year-olds, almost every day

2012
53%
2020
42%
2022
39%

Ages 5 to 8, read or read to, daily

2020
63%
2024
52%

Sources 16 and 22.

Teens: what the habit becomes

Half of American teenagers spend four or more hours a day on screens outside schoolwork. A picture book does not reach a fifteen-year-old, but the person buying for one is the same person buying for a six-year-old.

Symptoms in the past two weeks, ages 12 to 17 CDC, 2021 to 2023

Anxiety symptoms

4+ hrs/day
27.1%
Under 4 hrs
12.3%

Depression symptoms

4+ hrs/day
25.9%
Under 4 hrs
9.5%

50.4% of US teens are in the four-hour group24

The dose, and what teens say about it
4.8 hrs
a day on social media, average US teen. Girls 5.3, seventeen-year-olds 5.828
2.39×
the risk of suicidal behaviour on a high addictive-use path, ages 9 to 14. Total screen time alone was not linked23
32 → 48%
of teens say social media is mostly negative for people their age, 2022 to 20245
27 → 14%
of thirteen-year-olds read for fun almost daily, 2012 to 202322

Young adults: the first cohort raised on it

They are the only group who can say what it was like, and they are saying it. They also buy books for themselves.

13 → 24.6%
currently depressed, US adults under 30, 2017 to 202335
61%
of 18-to-25s report serious loneliness, against 36% of all Americans34
23%
of under-25s show problematic smartphone use. 41 studies, 41,871 people36
83%
have tried to cut back on social media. 60% back no smartphones until high school37
Gen Z who wish it had never been invented Harris Poll, Aug 2024, ages 18 to 27
X
50%
TikTok
47%
Snapchat
43%
Social media overall
40%
The smartphone itself
21%

Source 37.

Adults: the co-reader, forty years on

The grown-up on the other side of the book is inside the same problem. That is the second audience, and it is a buyer in its own right.

6h 38m
online a day, average adult internet user worldwide. About 40% of waking life41
205
phone checks a day, average American40
43%
of Americans consider themselves addicted to their phone. That is the adult layer in the model below40
54.6 → 48.5%
of US adults read at least one book a year, 2012 to 202222
How lonely US adults cope APA Healthy Minds, Mar 2025
TV, film, online video
63%
Music
57%
Talk to friends or family
49%
Sleep
47%
Social media
46%

A lonely adult reaches for a screen before they reach for a person, at nearly the same rate.38

They already buy books to do this job

Three quarters of parents have used a children's book to work a child through something. The behaviour exists. It does not have to be created.

90%
of parents agree books open up conversations44
74%
have used a children's book to help their child with something44
73%
say their children could use a detox from technology53
10 hrs
a week spent hunting for things to do that are not screens. 60% look to reading54
How picture books are bought Nielsen, 2015 — dated, direction still holds
Say about half their kids' book buys are impulse
53%
Say most are impulse
26%
Do no research at all before buying
60%
Children's book sales that are print
72%

For under-sevens the illustrations, packaging and price decide it. The cover is the sales pitch47

The million word gap Words heard from books by age five
Five books a day
1.48M
One a day
297K
Three to five a week
170K
One to two a week
64K
Never read to
4,662

Source 45. Also: 70% of kids name a teacher or school librarian as the person who got them reading for fun, and 63% get most of their books from a library.44

Everything is counted. Switch off what you don't believe.

Starts with the whole market and every revenue line on. Switch a setting off and watch the numbers move. Nothing here is a forecast; the three dashed lines are assumptions, not sourced data.

Book 1 market ceiling $0
What a share of it is worth0.01% to 10% of the ceiling, book 1 only

For calibration: the best-performing self-published screen-time picture book has 63 Goodreads ratings. The Caldecott honoree in the same category has 11,174.59

Ten years, five titles one launch every two years

Each bar is that year's new title stacked on the books still selling underneath it. Tap a year for the split.

Book 1 Book 2 Book 3 Book 4 Book 5 Media Film, from year 4
$0
Ten-year revenue, all five titles
$0
Best single year
$0
From books
$0
From merch, media and film
$0
Of year 10, from books 1 to 4 still selling
Settings
Reader segments
Revenue lines
The book, counted at
Each title captures
Hold it against real markets
Screen-free kids' activities, global, 2025
$35.4B
Children's books, global, 2025
$11.2B
US children's and YA fiction, publisher revenue, 2025
$5.4B
Picture books, the segment book one sits in
$3.2B
US toy market, for the merch line
$41.4B

Sources 48, 13, 60 and 61. The screen-free activities market is forecast at $61.4B by 2034 and names screen-time worry as its first growth driver. US toy sales rose 17% in the first half of 2026, the strongest start in six years. The merch, media and film lines above are the only three numbers on this page I made up rather than found; all are marked with a dashed border. Merch and media are deliberately conservative. Film is the one line that is binary: it is either zero or it dwarfs the books, and $1.5M a year is a single modest deal averaged flat, not a hit. Media in particular is a funnel, not a business: at any capture rate above 0.5% the channel earns less in a year than the books do in a month.

Sources

Every figure is dated at collection. Nearly all are associations, not demonstrated causes; the phrasing throughout is "linked to", never "causes". Numbers 1 to 51 match the Why B0b Matters sheet so the two agree.

  1. Mott Poll, top health concerns for 2025, Aug 2025. n = 2,021 US parents of children 1 to 18.
  2. Mott Poll, overuse of devices and social media top parent concerns, Aug 2023.
  3. Mott Poll, bullying and internet safety top concerns, Aug 2017.
  4. AJMC coverage of the 2025 Mott Poll.
  5. Pew Research Center, Teens, Social Media and Mental Health, Apr 2025.
  6. Pew Research Center, How Parents Manage Screen Time for Kids, Oct 2025.
  7. HarperCollins UK and NielsenIQ BookData, Dec 2024 report, via Motherly.
  8. AP via Fortune, school phone restrictions, Aug 2025. 35 states as of Aug 2025.
  9. SBS Dateline, Smartphone Free Childhood, Jan 2025.
  10. Market Intelo and Deep Market Insights, children's book market, 2025.
  11. Common Sense Census: Media Use by Kids Zero to Eight, published Feb 2025, data collected Aug 2024. n = 1,578, ±2.9%.
  12. Common Sense Tweens and Teens Census, 2021. No tween or teen census has been published since.
  13. Takahashi et al., JAMA Pediatrics 2023. 7,097 children, Japan.
  14. Vasconcellos et al., Psychological Bulletin 2025. 117 studies, about 293,000 children under 10.
  15. NEA, federal data on reading for pleasure, 2024, drawing on NAEP and the Survey of Public Participation in the Arts.
  16. Addictive screen use trajectories, JAMA 2025. 4,285 youths, ages 9 to 14.
  17. CDC NCHS Data Brief 513, US teens 12 to 17, 2021 to 2023.
  18. Gallup, teens and social media hours, Oct 2023.
  19. Harvard Making Caring Common, Loneliness in America, Feb 2021.
  20. Gallup depression survey, May 2023.
  21. King's College London, BMC Psychiatry 2019. 41 studies, 41,871 people.
  22. The Harris Poll, Gen Z on social media and smartphones, Aug 2024.
  23. APA Healthy Minds, loneliness, Mar 2025.
  24. Stacker and Spokeo, Americans' mobile habits 2025. Reported secondhand; the 43% self-described addiction figure is self-report, not clinical.
  25. DataReportal, Digital 2025.
  26. Pew Research Center, fielded 13 to 26 May 2025, published 8 Oct 2025. n = 3,054 US parents of children 12 and under, ±2.2pp.
  27. Scholastic Kids & Family Reading Report, key findings.
  28. Logan et al., the million word gap, Ohio State, Apr 2019.
  29. Nielsen, children's book purchases are rarely planned, 2015. Dated; direction likely still holds, exact percentages do not.
  30. Fortune Business Insights, Screen-Free Kids Activity Market. $35.4B in 2025, $61.4B by 2034.
  31. US Surgeon General advisory, 20 May 2026. Under 6: less than 1 hour a day. Ages 6 to 18: up to 2 hours. Non-binding.
  32. Bright Horizons / Harris Poll, Feb 2025. n = 2,000 including 622 parents.
  33. Talker Research for Lowe's, Jan 2026. n = 2,000 millennial and Gen Z parents.
  34. Age bands. Built from NCHS annual births as a cohort proxy for the resident population in late 2026. Ages 0 to 4, births 2022 to 2026: 18,099,000. Ages 5 to 10, births 2016 to 2021: 22,619,000. Ages 11 to 18, births 2008 to 2015: 32,183,000. Births understate slightly, since net immigration at these ages exceeds mortality.
  35. Classrooms: derived, not sourced. NCES Digest 203.10, fall 2023: PreK 1,574k, K 3,501k, grade 1 3,486k, grade 2 3,613k, grade 3 3,544k = 15.7M public students, at an assumed 20 per class. NCES CCD 2023–24 counts 51,654 regular public elementary schools and 3,253,091 public school teachers across all grades. True PreK–3 classroom count is likely 750,000 to 850,000.
  36. IMLS Public Libraries Survey: approximately 9,000 public libraries operating approximately 17,000 outlets.
  37. World Bank, 2024: 781 million children in primary education worldwide. An arithmetic ceiling only; it assumes translation, distribution and purchasing power that do not exist.
  38. Goodreads rating counts, collected Sep 2026. Amazon was unreachable at the research proxy, so Best Sellers Rank was not available.
  39. AAP StatShot Annual, Aug 2026: US children's and YA fiction publisher revenue $5.4B for CY2025. Per-unit economics from the project P&L at the 17 Sep 2026 channel mix: blended net about $7.00, direct hardcover net $14.33. US adult population from Census Vintage 2025: 341,784,857 total less 72,021,348 under 18.
  40. Circana via Newsweek, Sep 2026: US toy sales up 17% in the first half of 2026. Market size shown is the US total toy market, used only as context for the merch line.
  41. Merch and media: assumptions, not data. Merch at $1.00 net per book sold, from a 10% attach on a $9.99 coloring book at $4.00 net and a 5% attach on a $24.99 plush at $12.00 net. Media at 50M annual views and a $2.00 RPM, which is a mid-range figure for children's content where COPPA bars personalised advertising. Neither has been tested. Both are shown with a dashed border throughout.
  42. The ten-year model. Five titles launching in years 1, 3, 5, 7 and 9. Each sells its lifetime run on a decaying curve: 35% / 25% / 15% / 10% / 7% / 4% / 2% / 1% / 0.7% / 0.3%. The curve shape is a convention for illustrated backlist, not a measured figure for this book.
  43. Hutton, Dudley, Horowitz-Kraus, DeWitt and Holland, JAMA Pediatrics, Jan 2020. 47 children aged 3 to 5, diffusion tensor imaging. Higher ScreenQ scores linked to lower fractional anisotropy in the arcuate, inferior longitudinal and uncinate fasciculi; expressive vocabulary, emergent literacy and rapid naming lower. Behavioural associations weakened once household income was added. Cross-sectional.
  44. Law et al., JAMA Pediatrics, 31 Jan 2023. GUSTO cohort, Singapore, 506 children. Screen time at 12 months by parent report, EEG at 18 months, attention and executive function at age 9. Longitudinal; association.
  45. Madigan, Browne, Racine, Mori and Tough, JAMA Pediatrics, Jan 2019. All Our Families cohort, Calgary, 2,441 children. Mean 17.1 hours a week at 24 months, 25.0 at 36. Higher screen time predicted lower ASQ-3 scores at the next wave; the reverse did not hold.
  46. Madigan, McArthur, Anhorn, Eirich and Christakis, JAMA Pediatrics, Mar 2020. Meta-analysis, 42 studies, 18,905 participants. Screen quantity r = −0.14; co-viewing r = 0.16; later age at onset r = 0.17; educational content r = 0.13.
  47. Paulus et al., NeuroImage 2019, vol. 185. ABCD study, 4,277 children aged 9 to 10 with usable structural MRI. Screen media activity factors linked to cortical thickness, sulcal depth and grey matter volume; small associations with lower fluid intelligence and higher externalizing scores.

Gaps worth naming. No published sales data exists for screen-time picture books as a category. No controlled study links cover composition to children's book sales. The 8-to-12 and 13-to-18 screen-time figures are four years older than the under-8 data. Market sizes are analyst estimates and vary widely between firms.