Is There a Science to Finding the Right Book?

By Marian Wilde , GreatSchools Staff

The reading sweet spot is that perfect balance between a child's ability and a text's difficulty, that place where a child can skim across the page without realizing she's decoding symbols into ideas and stringing them together to create meaning.

It should be an experience of ease and comprehension.

Over the past several decades many systems have evolved with the goals of measuring the reader and the text. But, how accurate are they?

Readability Measures

Researchers have been working on readability measures since at least the 1940s. In the United States, the measure in the widest use is the Lexile Framework, which has been adopted by book publishers, educational testing companies and state Departments of Education.

The Lexile Framework measures a text by analyzing sentence length and word frequency. Once these factors are determined, they're fed into the Lexile equation and, presto, chango!, we have the Lexile ranking, a number ranging from 200L for beginner texts up to 1700L for advanced ones.

How Is The Lexile Framework Different From Other Measures?

What makes the Lexile Framework unique, and what has led to its widespread adoption, is that it also measures the reader. "Readability formulas have been around for at least 50 years, but no one had ever put the reader and the text on the same scale like we did," says Malbert Smith, president of MetaMetrics, the developer of the Lexile Framework.

"We actually linked with the state tests so that whenever they report out their scores they can also report out a Lexile measure on the student," says Smith. "When we developed the Lexile Framework we really wanted to give something to parents that would be actionable. Parents don't know how to take action on a "stanine" or a "NCE score" or a "percentage rank."

"Once you know your child's Lexile measure, you can come to our Web site, where we have 110,000 books that we've measured. The Lexile database is updated with new titles every month," continues Smith.

How to Find Your Child's Lexile Rank

Lexiles are used in some fashion in every state, although not all students in a state are measured. "In the U.S. there are about 52 to 53 million students in the K-12 space in public schools. About 25 million of those students get a Lexile measure from one of the test publishers," says Smith.

Find out how your state uses The Lexile Framework.

California does things a little differently in that the results of its Standardized Testing and Reporting (STAR) program are mailed to parents with the Lexile measure reported as a "California Reading List Number." A parent can use their child's Reading List Number when referring to a list of leveled books on the California Department of Education Web site.