HIP is very proud of the readability standards applied to all our books. While we cannot make teachers readability experts in one long web page, this may explain what we do at High Interest Publishing. Answers have been supplied by Paul Kropp, an authority on materials for reluctant readers.
Q: What is readability?
A: Readability is a measure of how hard it is to read a text. 
Measurement of readability ordinarily involves three factors: sentence length, syllable count and difficult vocabulary. The Fry readability graph uses the syllable count and sentence length of three 100-word passages to come up with a fairly reliable grade-level measure.
Q: Surely there are easier ways.
A: Yes, and harder ones. The Harris-Jacobson and Lexile systems are both more complex, but the results rarely differ much from Fry. Your computer will also calculate readability using the Flesch-Kincaid index and give results very similar to Fry. Go to Tools, Spelling and Grammar (use your options to set this to "casual" style), go through all the spelling and grammar queries, and the Flesch-Kincaid readability grade comes up at the end. (Careful, it can be thrown off by words with many vowels, just as the more complex systems can be thrown off by Canadian spellings or words like “ Ontario.”) Of course, all of these systems measure average readability, a procedure which isn't good enough for reluctant readers (see below).
Q: How does HIP do readability control?
A: After all the student testing and editorial revision is done (because the appeal of story and characters is even more important than readability), we recheck each page of text with both Flesch-Kincaid and the Fry. Then we check vocabulary against our own list of words (the HIP 800) usually known by readers at the grade-3 level who are in grades 5 to 8. A computer program rechecks the readability of each chapter using three different readability formulae, then highlights all the potentially difficult words. We use this information to reexamine the text.
We look first for sentence complexity – because simple sentences are easy to decode, compound slightly more difficult and inverted complex the most difficult. Then we look for “kernel,” the distance between a sentence's subject and verb. Finally, we reexamine each word that caused student readers to have difficulty. Is that word essential? Is it phonetically decodable. If so, can we make the meaning clear in context? Can it be replaced with an easier word?
Finally, we have young readers read the books aloud so we can listen for problems that come up in oral reading or deal with questions they may have. Fifty years of readability theory is important, but so are real kids.
Q: Why do you put so much effort into this?
A: Because readability control matters to reluctant readers. An ordinary student knows that he can go back and reread, or take notes, or ask for help if the text or vocabulary becomes too difficult. For that reason, an average readability level is good enough to help match an average reader with a book.
Reluctant readers, however, do not have the reading "fix-up" strategies that will let them access even a small section of difficult text. If you remember using an old tape recorder to make a recording, it wasn't the average volume that mattered; it was the peak volume that blurred the recording. For reluctant readers, it is the "peak" sections of difficulty that discourage them and lower comprehension.
For this reason, the key to real hi-lo books is that the text is reliably easy to read, page after page. Other publishers simply do a whole-book average readability, or take an educated guess. We don't think that's good enough. At HIP, we do not allow sudden shifts in difficulty levels between pages, or a difficult vocabulary word if it's not essential to the text. We want our reluctant readers to read each page with confidence – that means reading 95% to 100% of the words with relative ease.
Q: Is readability the same as leveling?
A: No. Readability is one aspect of leveling (Marie Clay, Fountas & Pinnell, etc), but only one aspect. Many other aspects of the story, the text and its presentation also make a difference.
Q: Is readability a guide to appropriateness by grade level?
A: No. Appropriateness by grade level involves the story, the characters, the situations and the presentation; it relates to the curriculum goals at a grade level and the maturity of the students. Our book Street Scene can be read by most grade 3 students, but it is not appropriate for any child in the primary grades. Conversely, Charlotte's Web has sections with very difficult vocabulary and readability at the grade 7-10 level, but is frequently read by very young students...with parent or teacher assistance.
Q: Should teachers care more about readability?
A: Definitely. In every subject area, including language arts, I see students struggling with books that are too difficult for them. Children need bulk reading of easy books to consolidate their reading skills, they need challenging reading with teacher support to extend their skills, but they should never face frustration-level reading in any subject.
