When I attended elementary school in California, I remember the classrooms using a Lexile framework to grade reading. In 1989, research company MetaMetrics developed Lexile levels, an interpretive measure of student growth in reading. MetaMetrics calculates a Lexile text measure by dividing a book into 125-word sections to analyze for word frequency and sentence length.

More recently another framework for books, called ATOS, emerged from software and analytics learning company Renaissance Learning. The ATOS book level, ranging from 0.1 to 20.0, takes into account average sentence length, average word length, and average word difficulty level.

ATOS developed from Renaissance Learning’s Accelerated Reader (AR) Program, an online software that offers quizzes for thousands of books and awards reading points for taking and passing the quiz for a corresponding book. It aligns with the ZPD, the Zone of Proximal Development, which uses the grade equivalent estimate of a student to place his or her reading level in an approximate range. My school also used this program.

For an example of how Lexile text measures, the ATOS book level, and the AR Program come together, consider Charlotte’s Web, by E. B. White.

Lexile text measure 680L, ages 7-9
ATOS book level 4.4 book level (BL)
Accelerated Reader Program 5.0 points

According to these measures, Charlotte’s Web would be textually difficult enough for 7-9 year olds, readers with literacy skills equivalent to the average 4th grader, and 3rd or 4th graders. The Accelerated Reader Program also determines Interest Level (IL). IL differs from BL in that it factors in age appropriateness of the story. Charlotte’s Web has an IL of MG 4-8.


Since their inceptions, American public schools have widely used these measurements – Lexile, ATOS, AR, and ZPD, among others – to gauge students’ literacy and assign grade- and age- appropriate reading. However, as with any question of children’s education, experts, educators, parents, and students themselves debate the merits of reading levels.

Reading achievement

On the one hand, investigations in the last decade have found that graded reader programs enhance students’ reading progress. For example, in 2011 100% of the third, fourth, and fifth graders from ABC Elementary School in southwest Texas who achieved their AR goal passed TAKS-Reading, a measurement of student mastery of state-mandated curriculum.^{[1]}

Interestingly, another study on the reading achievement growth of fifth grade students, as measured by Terra Nova Testing, measured a statistically significant lower score among students enrolled in the AR program than those not enrolled.^{[2]}

Grade-level reading

Graded readers are touted as tools to help parents and teachers identify grade-level material for students. Rather than wonder what books would cover learning milestones for, say, second grade, they could reference the reading level recorded on an online reading assessment tool or written on the front cover of a book. Lexile measures, for one, match readability and reading ability to expedite the process of selecting reading material.^{[3]}

Some parents and teachers oppose this grade-matching system of Lexile levels and the like. Professor Stephen Krashen from the University of Southern California identifies restriction of reading as one potential harm of graded reader programs.^{[4]}

I volunteer weekly at my local library, and can attest to this unintended effect. Kids come into the library with their parents and must find a book that falls in their ZPD. They often reject perfectly wonderful novels because the books fall below grade level.

white teddy bear reading book
Photo by Pixabay on

Motivating readers

One of the goals of Lexile levels and the AR program was motivating readers. By offering quizzes to earn points, and oftentimes also classroom rewards, for reading achievements, students theoretically read more books and read more often. Whether this is achieved or not is another matter.

One analysis of over 1,500 middle school students found those exposed to AR actually read significantly less than those not in AR, as determined from reading diaries or logs.^{[5]} Some educators and researchers question if AR makes “lifelong lovers of reading or students who are merely addicted to earning points and prizes.” ^{[6]} High schoolers at one underperforming school blamed the implementation of AR, including perceived “forced” reading and the stress of earning points, to a growing aversion to recreational reading. ^{[6]}

A study that investigated the students’, teachers’, and administrators’ perceptions of the AR program in one school district provides some proof for the fear that graded reading programs create point-seekers and not passionate readers.^{[7]} Several students admitted to choosing quicker, “easier” books to read so that they could earn the points.


Graded readers may help educators connect students to age- and grade-appropriate material, but research on the effects challenge program claims from AR, Lexile Framework, and others to promote student reading. In fact, these programs might be turning students away from reading!


What do you think of applying reading levels to books in school?

[1] Keyim, Hasiyet. The Impact of the Accelerated Reader Program on Elementary Students’ Reading TAKS Scores in an Urban Predominantly Hispanic Title I School. 2011. University of Houston, EdD dissertation.
[2] Melton, C.M., Smothers, B.C., Anderson, E., Fulton, R., Replogle, W.H. & Thomas, L. (2004). “A Study of the Effects of the Accelerated Reader Program on Fifth Grade Students’ Reading Achievement Growth.” Reading Improvement 41.1 (2004). LearnTechLib, n.d.
[3] Stenner, A. J. “The Lexile Framework: A Common Metric for Matching Readers and Text.” California School Library Association Journal 25.1 (2001); 41-42. Western Oregon University, n.d.
[4] Krashen, Stephen. “The Lexile Framework: Unnecessary and Potentially Harmful.”  ResearchGate, 2014.
[5] Pavonetti, Linda M., K. M. Brimmer, and J. F. Cipielewski. “Accerelated Reader (R): What Are the Lasting Effects on the Reading Habits of Middle School Students Exposed to Accelerated Reader (R) in Elementary Grades?” ERIC, 2000.
[6] Thompson, Gail, M. Madhuri, and D. Taylor. “How the Accelerated Reader program can become counterproductive for high school students.” International Reading Association 51.7 (2008): 550-560. Book Love Foundation, n.d.
[7] White, W. Q. “An Investigation of the Accelerated Reading Program in One Small School District: Students’, Teachers’, and Administrators’ Perceptions.” 2005. The Ohio State University, PhD. dissertation.