The children’s book market is a complex, crowded beast filled with nuance and lingo that can be intimidating for authors looking to break into this space. But the first thing that any debut or established children’s book author should understand when developing their manuscript is the difference between the main book categories that make up children’s literature.

First things first: What are children’s books categories? Different than genre (i.e., fantasy, biography, contemporary fiction, etc.), these book categories are age-based groupings that reflect the reading level and maturity of readers. Think a picture book versus a chapter book. Each category can contain books of any genre, but they will differ in terms of the target-audience age; length; complexity of the language, plots, and themes; and requirements for artwork.

With the children’s market being unique in that the target readership will vary widely in maturity and reading levels, parents and teachers rely heavily on the conventions of established book categories to identify appropriate reading material for their kids, and most bookstores, libraries, and online retailers will shelve children’s books based on these categories. Therefore, if a book strays too far from the standards of its intended category, it will likely be difficult to appeal to the target readers and reach a viable audience. Having a good grasp of the conventions of the category you are writing for is critical in determining many of the choices you make while developing your manuscript.

So here’s a breakdown of the seven categories to help you decide which is appropriate for your manuscript and guide your decisions as you develop it.

Board Books

Board books are babies' first books that are meant to help build vocabulary, language comprehension, and early literacy skills. These books are tactile and durable to withstand toddlers' rough handling, usually printed on tough, cardboard-like material. They can be novelty books, which include extra interactive elements such as pop-ups, texture, sound buttons, and other effects that help build meaningful connections for early childhood development.

• Age Range: 0–4 years
• Length: 0–300 words
• Plot and Arc: plot isn’t necessary but should be very simple if included
• Themes: basic learning concepts such as opposites, counting, shapes
• Language: very simple, repetitive text
• Artwork: included throughout and has an important role in telling the story
• Examples: Moo, Baa, La La La!; Baby University series

Picture Books

Picture books are books in which the text and illustrations work together to tell a story. These books are meant to be read aloud by an adult.

• Age Range: 2–8 years
• Length: 0–600 words; most commonly the final book is 32 pages
• Plot and Arc: one simple arc, one main character, and one plot; should pose a question that is answered by the end of the book
• Themes: situations preschool/early elementary children can relate to; life lessons related to emotional intelligence, relationships, morals, and social conventions
• Language: meant to be read aloud so should utilize rhythm, cadence, and/or repetition; most of the text dedicated to dialogue and actions
• Artwork: included throughout and equally, if not more, important than the text in telling the story; should illustrate more than what the text is saying
• Examples: The Very Hungry Caterpillar, The Color Monster

Illustrated Children’s Books

Illustrated children's books, for the most part, are longer and rely more heavily on text than picture books. Usually covering nonfiction topics, these books are most commonly anthologies, almanacs, or encyclopedic-type books. While still often read aloud by adults, young readers may grow into reading these independently

• Age Range: 5–12 years
• Length: 0–10,000 words
• Plot and Arc: room for more complexity
• Themes: slightly older themes and can tackle more difficult problems as long as it’s done with sensitivity
• Language: less reliance on playful prose than with picture books; since often read with adults, language can be more complex
• Artwork: included throughout but should be supplementary to the story, illustrating what the text shows
• Examples: Dragonology, DK Children’s Anthologies

Easy (Early) Readers

Early reader books are intended for children just learning to read by themselves. The language and plots need to be kept very simple, even more so than for picture books, as kids need to be able to understand with limited or no adult guidance. These books are usually targeted to schools and librarians, and most of the time these will be written by publishers rather than individual authors. Purchasers expect a very low price point and gravitate toward known publishers in this space.

• Age Range: 5–8 years
• Length: 1,000–3,000 words
• Plot and Arc: very simple plots; character arc isn’t necessary
• Themes: explore one idea, subject, or theme; topics should be light-hearted and relatable to children of this age
• Language: very simple, tightly controlled, and accessible to the target reading level; primarily action and dialogue in text with minimal description; story can be broken into brief chapters to allow readers to take a break
• Artwork: included throughout but supplementary, illustrating what the text shows as a comprehension aid
• Examples: Danny and the Dinosaur, National Geographic Kids Readers

Chapter Books

For young advancing readers, chapter books bridge the gap between an early reader book and a full novel. Read independently or with adult support, chapter books may contain occasional illustrations and often appear in a series. Since reaching a child’s specific reading level is still so critical in this category, purchasers tend to prefer publishers and series they know that can meet their young readers’ abilities, making this a difficult category for new authors to break into.

• Age Range: 6–10 years
• Length: 5,000–15,000 words
• Plot and Arc: fast-paced plots that can be more complex with one or two subplots; main character should have an arc
• Themes: usually about school problems and other age-appropriate concerns; focus almost exclusively on external conflict
• Language: more complex language but should still be controlled for age group; beyond just action and dialogue, brief descriptions of settings, characters, emotions, etc., can begin to come in; usually divided into short chapters
• Artwork: occasional artwork may be included to hold readers’ attention and act as a comprehension aid
• Examples: Magic Tree House series, Who Was? series

Middle Grade

Middle grade books consist of short but fully developed novels and works of nonfiction. Readers of middle grade are ready to dive into reading independently, and reading becomes less about developing a skill than experiencing the joys of a good book.

• Age Range: 8–12 years
• Length: 20,000–50,000 words
• Plot and Arc: complete three-act structure, slower paced than chapter books with more emotion and mystery; more complex character arcs; multiple subplots
• Themes: age-appropriate challenges and concerns but more complex themes; humor is common; superficial violence and, for the most part, pre-romance; focused more on character’s reaction to their world than self-reflection
• Language: longer chapters; more description and emotion
• Artwork: often not included
• Examples: Percy Jackson and the Olympians series, Plague-Busters!

Young Adult (YA)

Young adult literature describes works written for teenagers and characterized by self-reflection and internality. They are longer and cover more mature themes than middle grade books.

• Age Range: 12–18 years (though many adults also enjoy reading YA)
• Length: 50,000–80,000 words
• Plot and Arc: complete three-act structure with at least two subplots; character arc is very important
• Themes: often a coming-of-age story about identity, self-discovery, and the transition to adulthood; romance (but not eroticism) and violence (can be graphic but shouldn't be gratuitous) are common; highly introspective
• Language: faster paced than adult fiction with slightly less description; no vocabulary limits; schools and libraries may have acquisition criteria that screen out mature themes and language
• Artwork: often not included
• Examples: The Hunger Games, All Boys Aren’t Blue

Now that you have a good handle on the various types of books that exist within the children’s literary market, we want to leave you with a few key considerations to ensure your manuscript aligns with the standards of its category and to avoid problems for the book down the line. As you are writing and editing, check to make sure that your manuscript is not veering from the intended category in any of the following ways:

• Word count is too high
• Word choice is too advanced or not advanced enough
• Subject matter and themes are too mature or immature
• Main character’s age is too young (One thing to note here is that most kids like to read about characters a couple years older than themselves and will rarely want to read down. So while middle grade books will be read by kids 8–12 years old, most middle grade protagonists will be 11–13 years old and should not be 7 years old or younger.)
• Artwork does not function based on the needs of the category

If you’re interested in exploring next steps for your children’s manuscript and potentially receiving more information on how it meets the conventions of a children’s book category, you can submit your work for consideration here: greenleafbookgroup.com/submissions.