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.

Criticism of the Lexile Framework

The Lexile Framework has its detractors, such as Stephen Krashen, Emeritus Professor of Education at the University of Southern California. Krashen asserts that the money states are spending on The Lexile Framework would be better spent on acquiring books for schools and districts with limited financial resources. Teachers and librarians, he says, are already trained to match readers with books and don’t need the added nuisance of readability formulas.

Other critics have cited the fact that readability formulas measure only a handful of factors that affect text difficulty. Factors not measured are number and organization of concepts, degree of abstraction of these concepts, length of paragraphs and the complexity of punctuation.

A simplistic way of measuring texts can lead to disconnects with reality. Say, for example, that your child has just devoured The Lion, The Witch and The Wardrobe. Eager to cultivate her passion for reading you consult the Lexile database and find that this book clocks in with a Lexile ranking of 940L. The Fellowship of the Ring, another classic of the fantasy genre, would be a good choice, you think. Discovering that it’s Lexile ranking is 860L, you happily locate a copy, reasoning that giving her an easier book to read will increase her sense of mastery.

Unfortunately, it won’t be long before you, and your daughter, discover that The Fellowship of the Ring is much harder to read than The Lion, The Witch and The Wardrobe. This is an example of what happens when you ask a computer to analyze literature.

The research department at the Lexile Framework responded to our hypothetical situation with this comment, “The Lexile Framework for Reading, as a readability formula, focuses on two features: semantic and syntactic characteristics of the text. A properly ‘matched’ student will not have trouble with the semantic and syntactic demands of the text. As a readability formula, the Lexile Framework does not take into consideration factors such as developmental appropriateness, conceptual complexity or allegorical demands. For example, that is why the Lexile Framework is not recommended for the measurement of poetry.”

A simpler way

For parents looking for a simpler way to help their child choose a book, award-winning teacher Jennifer Thompson recommends the “five-finger test.” “Have your child open the book to any page,” says Thompson, a GreatSchools consultant. “If they find five words that they do not know; the book is too difficult.”

A precision tool

“If I’m a school nurse and a student comes in complaining of a headache,” says Smith, “I can do a very primitive assessment. I can take the back of my hand and put it on his forehead and see if he feels hotter than I feel and I can infer if he has a fever. If I wanted to be more precise, though, I’d take a thermometer and get his temperature.”

Although the Lexile Framework claims to be a precise measure of a reader’s ability and a text’s readability, it is not a panacea. A child’s interest and enthusiasm for a subject must also be taken into account.

Smith concurs: “If a child wants to read about basketball and we give him books about soccer, he’s not going to read it even though the text is accessible to him and it’s at the right level. So you still have to pay attention to interest level. And you still have to pay attention to developmental appropriateness.”

The Lexile Framework is simply one more tool in the parent’s toolbox.