A Lexile measure is a valuable piece of information about either an individual's reading ability or the difficulty of a text, like a book or magazine article. The Lexile measure is shown as a number with an "L" after it — 880L is 880 Lexile.
It is important to note that the Lexile measure of a book refers to its text difficulty only. A Lexile measure does not address the content or quality of the book. Lexile measures are based on two well-established predictors of how difficult a text is to comprehend: word frequency and sentence length. Many other factors affect the relationship between a reader and a book, including its content, the age and interests of the reader, and the design of the actual book. The Lexile measure is a good starting point in your book-selection process, but you should always consider these other factors when making a decision about which book to choose.
Lexile Measures Help Readers Grow, and Help Parents and Teachers Know
Teachers and parents can best serve a student's literacy needs when they treat him or her as a unique individual, rather than as a test score or a grade-level norm or average. The reading abilities of young people in the same grade at school can vary just as much as their shoe sizes. However, grade-leveling methods commonly are used to match students with books.
When a Lexile text measure matches a Lexile reader measure, this is called a "targeted" reading experience. The reader will likely encounter some level of difficulty with the text, but not enough to get frustrated. This is the best way to grow as a reader—with text that's not too hard but not too easy. ...continued here