What is a Lexile Measure?

The Lexile Framework for Reading is an educational tool that uses a measure called a Lexile to match readers of all ages with books,  articles and other leveled reading resources. ^[1]

A book, article or piece of text gets a Lexile text measure when it's analyzed by MetaMetrics. For example, the first "Harry  Potter" book measures 880L, so it's called an 880 Lexile book. A Lexile text measure is based on two strong predictors of how difficult a text  is to comprehend: word frequency and sentence length. ^[2]

Recognized as the most widely adopted measure of reading ability, more than 28 million Lexile measures are reported from reading programs and assessments annually.^[3] Thus, about half of U.S. students in grades 3rd through 12th receive a Lexile measure each year.^[4] Lexile measures are being used across schools in all 50 states and abroad.^[5]

Here is an example table from Wikipedia. Sambuka Black is located between Harry Potter and A Tale of Two Cities - how incredibly appropriate.

Title	Author	Lexile
The Cat in the Hat	Dr. Seuss	260L
Clifford the Small Red Puppy	Norman Bridwell	330L
The Very Hungry Caterpillar	Eric Carle	460L
The Giving Tree	Shel Silverstein	530L
Charlotte's Web	E. B. White	680L
Twilight (novel)	Stephenie Meyer	720L
Where the Wild Things Are	Maurice Sendak	740L
Harry Potter and the Philosopher's Stone	J. K. Rowling	880L
A Tale of Two Cities	Charles Dickens	990L
The Hobbit	J. R. R. Tolkien	1000L
Gone with the Wind	Margaret Mitchell	1100L
A Brief History of Time	Stephen Hawking	1290L

References:

1. Wikipedia entry, http://en.wikipedia.org/wiki/Lexile

2. MetaMetrics, Inc. http://www.lexile.com/about-lexile/lexile-overview/

3. Hiebert, E.H. (2002). Standards, assessment, and text difficulty. In A. E. Farstrup & S. J. Samuels (Eds.)What research has to say about reading instruction (3rd Ed.). Newark, DE: International Reading Association..

4. "Facts for Features". US Census Bureau. Archived from the original on 27 June 2008.

 5. "Lexile Measures at Home". Georgia Department of Education. https://www.georgiastandards.org/resources/Documents/Lexile%20Measures%20at%20Home.pdf.