Measured Insights, August 2026

The Editor’s Note

Somewhere between the last page-turner and the first notification, many students stopped reading full books. Not because they can’t read, but because they don’t have the stamina to do so. Chapters have given way to snippets and plots to TL;DR. And some professors report a growing number of incoming college students who were never assigned a whole book in high school. 

The reasons for shifting away from whole book reading are still debated. What’s harder to dispute is the payoff: students who read whole books tend to have longer reading stamina and higher achievement levels. Maybe it’s time to dust off that copy of Harry Potter?

[Research] Beyond the Passage: Why What Students Read Matters

Developed in collaboration with the School of Education at the University of North Carolina at Chapel Hill and Doctoral Student and Graduate Research Assistant, Yuzi Gao, PhD in Education (Culture, Curriculum, and Teacher Education)

Educators often encourage students to read more, but does the type of reading matter? In a large longitudinal study, Jerrim, López-Agudo, and Marcenaro-Gutiérrez (2020) examined whether adolescents’ reported reading habits were associated with their eighth-grade reading and mathematics achievement after accounting for earlier achievement and a wide range of student and family characteristics. Their findings suggest that regularly reading books is more strongly associated with achievement in both subjects than reading several other types of materials.

What Did the Researchers Study?

The researchers analyzed longitudinal census data from students in Andalusia, Spain, who were in fifth grade in 2008-2009 and eighth grade in 2011-2012. The final sample included 45,160 students; 43,604 were included in the reading analyses and 43,833 in the mathematics analyses. Students reported how often they read comics, tales or short novels, books, magazines, and newspapers, outside school, using response options from “never or almost never” to “every or almost every day.”

The researchers examined associations between students’ reported eighth-grade reading habits and their performance on standardized Spanish-language and mathematics assessments, accounting for fifth-grade achievement, socioeconomic background, parental reading and educational involvement, students’ attitudes toward school, and differences associated with the primary and secondary schools they attended. 

What Did They Find?

• Book reading showed the strongest and most consistent association with academic achievement. After accounting for students’ earlier achievement and other background characteristics, students who read books daily or almost daily scored approximately 0.22 standard deviations higher in reading and 0.20 standard deviations higher in mathematics than students who rarely or never read books.
• For book reading, higher reported frequency was associated with progressively higher achievement. Compared with students who rarely read books, students who read books once or twice a month, once or twice a week, or almost daily scored approximately 0.12, 0.16, and 0.22 standard deviations higher, respectively, on the eighth-grade reading assessment. A similar pattern appeared in mathematics, where the corresponding differences were approximately 0.09, 0.12, and 0.20 standard deviations. 
• Reading short stories or short novels was also positively associated with achievement, but the relationship was smaller. Students who read short stories or short novels almost daily scored approximately 0.12 standard deviations higher in reading and 0.10 standard deviations higher in mathematics than students who rarely read them. Unlike book reading, however, monthly, weekly, and daily reading of short stories showed fairly similar adjusted associations, providing little evidence of a steadily increasing relationship with frequency. 
• Comics, newspapers, and magazines did not show similarly strong or consistent, positive associations with achievement. Their associations with reading achievement were generally small or close to zero after accounting for earlier achievement and other factors. Mathematics results were also small and, in some cases, negative. This finding does not mean these materials have no educational value. The authors examined their relationship with standardized reading and mathematics achievement, not their potential contributions to motivation, background knowledge, identity, or enjoyment.
• The association between frequent book reading and reading achievement was particularly strong among lower-achieving students. In additional analyses, students near the lower end of the reading achievement distribution who reported reading books almost every day scored approximately 0.35 standard deviations higher than students at similar points in the distribution who reported almost never reading books. The association became smaller toward the upper end of the achievement distribution. This suggests that the relationship between book reading and achievement may be especially relevant for students who are struggling with reading, although the finding remains correlational.

Why Might Books Make a Difference?

The researchers suggest several possible reasons why reading books may be more strongly associated with achievement. Books may expose readers to more challenging vocabulary and sophisticated sentence structures while requiring sustained attention and engagement. Compared with shorter materials that students can read in brief intervals, books may offer more opportunities to follow developing ideas, maintain coherence, and build understanding across extended texts.

These explanations are possible mechanisms rather than findings directly tested in the study. The researchers did not directly measure sustained attention, comprehension across lengthy texts, book completion, or the mechanisms underlying the observed associations. Therefore, reading stamina is a plausible interpretation of the findings, not an outcome the researchers directly assessed.

How Does This Connect to the Science of Reading?

Within broader reading research, these findings are best viewed as complementary to explicit instruction in foundational reading skills. Sustained engagement with books may provide opportunities for students to apply developing reading skills while engaging with longer, more complex connected text. 

The study did not evaluate science of reading instruction or identify which instructional approaches best support book reading. Its relevance is that developing skilled readers may require attention not only to reading skills themselves, but also to opportunities to engage meaningfully with extended texts. This connection is an interpretation of the findings rather than an instructional approach tested in the study. 

Implications for Educators

• Provide opportunities for sustained book reading. Include regular time for students to engage with complete books or other extended, coherent texts rather than relying exclusively on short passages.
• Encourage regular engagement. The authors found stronger academic associations among students who reported reading books more frequently, suggesting that regular engagement may matter more than occasional exposure.
• Support students as they engage with extended texts. Use read-alouds, shared reading, discussion, vocabulary support, and comprehension checks to help students maintain engagement and follow ideas across a longer text.
• Provide access to engaging books. Offer appropriately challenging and appealing texts so that students can find books that connect with their interests and experiences.
• Include extended-text opportunities for students who need additional support. Because the association between book reading and achievement was especially strong among lower-performing readers, ensure that these students also have opportunities to engage with longer texts, with appropriate support when needed.

What Should Readers Keep in Mind? 

Because students reported their reading habits in eighth grade, at roughly the same time their eighth-grade achievement was measured, the study cannot establish that reading habits preceded or caused the observed achievement differences. The findings should therefore be interpreted as associations rather than causal effects. In addition, the study focused on early adolescents from one region of Spain, so the results may not generalize to younger students or other educational settings. 

Relevance for the Lexile® and Quantile® Frameworks 

The study’s findings are relevant to both reading and mathematics, although the connection is more direct for reading. The Lexile Framework for Reading can help educators and families identify books and other texts that provide an appropriate level of challenge for individual students, complementing the study’s emphasis on regular engagement with books and extended texts. This may be particularly useful for students who need additional reading support, given that the association between frequent book reading and reading achievement was strongest among lower-achieving readers.

The connection to the Quantile Framework for Mathematics is more indirect. Jerrim et al. (2020) found that frequent book reading was also associated with higher mathematics achievement and suggested that reading skills may help students understand mathematical instructions and interpret problems that require reading comprehension. The Quantile Framework can complement this goal by helping educators connect students with mathematics skills, concepts, and resources at an appropriate level of challenge. The study did not evaluate either Framework, so these connections should be understood as practical applications of the findings rather than effects demonstrated by the study.

Read the study.

Reference: 

Jerrim, J., López-Agudo, L. A., & Marcenaro-Gutiérrez, O. D. (2020). Does it matter what children read? New evidence using longitudinal census data from Spain. Oxford Review of Education, 46(5), 515–533. https://doi.org/10.1080/03054985.2020.1723516

Turn the Page and Press Play: What We’re Reading and Listening To

[Article] Rebuilding Reading Stamina: Why Whole Books Still Matter, Freedom in Education, Beanie Geoghegan, June 1, 2026
Reading for fun and reading full books have fallen out of fashion. Reversing both trends requires building reading stamina and confidence. Think of it like Couch to 5k, but for reading. Beginning reader to bookworm, anyone? 

[Article] The Elite College Students Who Can’t Read Books (subscription required), The Atlantic, Rose Horowitch, October 1, 2024
Imagine showing up at college unprepared to read a book. It’s not that unusual, especially when students were never asked to read a full book in high school. If your jaw just dropped, you’re not alone. 

[Article] Novels vs. Excerpts: What to Know About the Big Reading Debate, Education Week, Sarah Schwartz, October 27, 2025
Whole books require a longer attention span than TikTok or YouTube. But excluding novels from school curricula isn’t new. There’s much debate about the right balance, but no definitive point of view. At least not yet.  

[Podcast] Building Reading Stamina: Strategies to Help Students Read for 30 Minutes or More, K-12 Greatest Hits, August 1, 2026
Which do we care about more—kids passing a reading test or that kids can read? Many times, the answer is the former. But is reading more the answer to increasing stamina? Many think it is.  

[Podcast] Whole Books or Excerpts? Which Do the Most to Promote Reading Ability?, Shanahan on Literacy, November 8, 2025
Nobody ever said excerpts, short stories, and articles are bad. But are they as effective as full books when it comes to improving reading stamina? Spoiler alert: the jury remains out. 

[Podcast] On Reading Whole Books, with Elizabeth Eames, Life of the Mind: Brookewood & Avalon Schools, March 3, 2025
The cultural moments of exciting “big fat books” like those in the Harry Potter series are rare today. As are classrooms that read full books. But when students spend more time in books, not only does stamina naturally increase, but insights do, too. 

Did You Know?

4-5 hours per day on social media. Less than 10 minutes reading.

This is the reality for most teens today. Is anyone else concerned? Cue the resounding “YES!”

83% of teachers in grades 3-8 report a decline in students’ reading stamina since 2019.

Are screens the culprit? Or the fact that fewer students are reading whole books? 

Two-thirds of middle- and high-school English teachers assign only 1-4 books per year.

Even worse, 9% assign none at all. It’s no wonder reading stamina is declining. 

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