What is a Lexile?
A Lexile measures both reading ability and text difficulty; it serves to connect a reader with an appropriate book. Similar to a pair of shoes, one size does not fit all when selecting a book. When recommending books based on age or grade level, some children would not be challenged while others may struggle with the same book. The Lexile measure serves to match a reader with an appropriate text.
A Lexile measure is typically a number followed by the letter, L. The Lexile scale ranges from below 200 (beginner readers) to above 1700 for advanced readers. A Lexile measure of zero or below, is coded with just the letters, BR, representing beginning reader. Reading tests are available to determine a reader’s Lexile measure. Using a proprietary equation, a book’s measure is calculated using both sentence length and word frequency. To assist both parents and educators, some books are assigned additional codes. The additional Lexile codes are as follows:
- AD (Adult Directed)
AD indicates these books, e.g. picture books, are typically read aloud to a child instead of a child reading this book independently for the first time. Preschoolers typically love read aloud books but if you take a closer look many of these books would present reading difficulties due to text, book layout or design, e.g. lack of detailed illustrations to support text.
- NC (Non-Conforming)
NC indicates these books have a higher Lexile measure than intended by the publisher. For example, an author writes a book about airplanes with a target audience of first through third grade. However, the Lexile measure (based on sentence length and word frequency) determines this book is higher than a typical elementary student’s reading ability. As a result, the book receives a “NC” before the Lexile number, e.g. NC750L.
- HL (High-Low)
HL indicates these books have a lower Lexile measure than the intended target audience’s reading ability. These books, e.g. young adult books, are often referred to as “high-low” books; they have “high-interest” but “low-readability.” For example, a book that contains short sentences and basic vocabulary, but discusses high school related topics, e.g. peer pressure, dating, would be categorized as HL or HL420L.
- IG (Illustrated Guide)
IG indicates these books contain independent pieces or sections of text, e.g. an encyclopedia or glossary. This book is typically not read like a storybook but rather used as a reference resource.
- GN (Graphic Novel)
GN indicates these books contain a graphic novel or comic book. These books contain mostly dialogue, e.g. thought bubbles, in lieu of traditional text conventions. For example, these books would contain a thought bubble above an illustration instead of writing, “He said, …”
- BR (Beginning Reading)
BR indicates these books are appropriate for a beginner reader; they are not used for independent reading but rather read aloud to an emergent reader. These books received a Lexile measure of 0L or below and are coded using just BR (no numbers).
- NP (Non-Prose)
NP indicates these books consist of 50% or more of non-standard or non-conforming prose, e.g., poems, plays, songs and recipes. Similar to BR, NP books do not receive a Lexile measure.
Selecting A Book
Matching a reader’s Lexile measure with a comparable text is referred to as targeted reading. Ideally a child should experience some reading difficulties but not too many. To avoid frustrating a child, select texts which are neither too easy nor too hard. Selecting books that range from 50L above or below your child’s Lexile measure typically result in a positive reading experience.