I attended Bonnie Bader's breakout session, Writing for the Transitional Reader. Early Chapter Books at the SCBWI Summer Conference because I wanted to know more about them.
I find it a confusing subject.
Bonnie clarified many things for me. I did some internet research to try fill in the gaps. As best I can figure out, this information varies by house, so take it with a grain of salt.
Leveled readers: Usually 32-48 pages. Leveled readers have a structured vocabulary.
The best known structured vocabulary list is is the Dolch List I've linked to the one that is alphabetical by grade.
This is taken from Mary Koles's Kid Lit.com
Early readers are the earliest “chapter” stories that a kid can get. They’re very short in terms of manuscript length (1,500 words max) but are broken up into either chapters or vignettes that will give the reader the feeling of reading a book with real chapters in it. Your target audience for these is kids ages 4 to 8. Early readers feature a smaller trim size, some the size of or slightly bigger than a paperback novel, and can go from about 32 to 60 pages. The font size is smaller and they feature spot illustrations in either color or black and white instead of full color throughout, like a picture book. Even if you think you have a great early reader idea, it has to be a very precise fit for a publisher’s established vocab/sentence/word count guidelines.
LING AND TING: NOT EXACTLY THE SAME by Grace Lin and Good Night Good Knight by Shelly Moore Thomas.
If you use the "look inside me" feature, you can get a very good idea of this format.
Bonnie's example was Young Cam Jensen, (a level three book) 4 chapters. Color illustrations Probably under 48 pages. But, I believe more words than Ting and Ling
Easy Chapter BooksThe Princess Posy series:
These books have 10 chapters, and black and white illustrations. They run 96 pages, 2400-3000 words per book - approximately 300 words a chapter. If you go to the link, you can see how the illustrations meld with the text, making some description unnecessary. "She slipped a spoonfull of green peas into Danny's mouth." (Yes you can add an art note to your manuscript Mom feeding Danny in High Chair.) The illustrations shows a mom feeding a baby in a high chair.
Henry and Mudge, by Cynthia Rylant. Color illustrations Seven chapters. 100 words per chapter. Average 25 words per page)
These are longer books. 29 chapters LOTS of black and white cartoon illustrations. about 185 pages long.
Boys and girls love this series.
You may have noticed these books are all series books. That's what publishers prefer. Is there room for a single book? Why, yes. Deborah Underwood's Pirate Mom is a stand alone level three reader published by Random House (Three chapters 48 pages color illustrations) I bought a copy at the SCBWI Summer Conference and I think it's hilarious and very accessible to young readers.
Early Chapter BooksThese are aimed at ages 7-9, Grades 2-4, depending on the level of reading competence. They run around 128 pages and 10,000 words. The illustrations are black and white and the number of them seem to vary by series. The characters are usually aged 8-10
Bonnie says George Brown Class Clown is about 10,000 words. Take a look at the layout.
The Author, Nancy Krulik, also writes the very popular Katie Kazoo, Switcheroo Katie looks to be a bit more word dense than George Brown,(smaller print. I counted 100 words on on page and 10 pages in the chapter.) but they are both listed for the same reading level.
My current favorite early chapter books is Clementine by Sarah Pennypacker and illustrated by Marla Frazee. This one breaks some rules. There is no Chapter 2. It goes from chapter 1 to chapter 3. I believe it is seven chapters for the days of her "not so good of a week. " I love the humor and the wonderful first person voice.
Another popular early chapter books is Judy Moody This one had 141 pages but many full page illustrations.
My friend and fellow author Nancy Stewart's blog post Early Chapter Books for Young Readers. mentions several books I want to check out.
I hope this clarifies a few things. If you want to look further for information on leveled readers, the best place I found was ReadingA-Z.com. Here's a link to their criteria for Early emergent readers, Level aa to Z. (phew!!) and here is the list of books that match their criteria. If you click on the books. you will see a picture and a word count. Levels aa-books have 17-24 word. Levels A-C seem to average 50 words and use a High frequency word list.
Happy writing and researching.