January 23, 2018

This is the second entry in the Education Leader’s Guide to Reading Growth, a 7-part series about the relationship between reading practice, reading growth, and overall student achievement.

In our last post, we examined how reading practice characteristics differ between persistently struggling students and students who start out struggling but end up succeeding—and how strong reading skills are linked to high school graduation rates and college enrollment rates.

However, it’s not just struggling readers who could benefit from more reading practice. A study of the reading practices of more than 9.9 million students over the 2015–2016 school year found that more than half of the students read less than 15 minutes per day on average.1

Students’ Average Daily Reading Time

Fewer than one in five students averaged a half-hour or more of reading per day, and fewer than one in three read between 15 and 29 minutes on a daily basis.

Few Students Read 30 Minutes or More

The problem is that 15 minutes seems to be the “magic number” at which students start seeing substantial positive gains in reading achievement, yet less than half of our students are reading for that amount of time.

15 minutes seems to be the “magic number” at which students start seeing substantial positive gains in reading achievement; students who read just over a half-hour to an hour per day see the greatest gains of all.

An analysis comparing the engaged reading time and reading scores of more than 2.2 million students found that students who read less than five minutes per day saw the lowest levels of growth, well below the national average.2 Even students who read 5–14 minutes per day saw sluggish gains that were below the national average.

Only students who read 15 minutes or more a day saw accelerated reading gains—that is, gains higher than the national average—and students who read just over a half-hour to an hour per day saw the greatest gains of all.

15 Minutes and Reading Growth

Although many other factors—such as quality of instruction, equitable access to reading materials, and family background—also play a role in achievement, the consistent connection between time spent reading per day and reading growth cannot be ignored.

Moreover, if reading practice is linked to reading growth and achievement, then it follows that low levels of reading practice should correlate to low levels of reading performance and high levels of reading practice should connect to high levels of reading performance. This pattern is precisely what we see in student test data.

Strong connections between reading practice and achievement

An analysis of more than 174,000 students’ Programme for International Student Assessment (PISA) scores revealed that connection between reading engagement and reading performance was “moderately strong and meaningful” in all 32 countries examined, including the United States.3 On average, students who spent more time reading, read more diverse texts, and saw reading as a valuable activity scored higher on the PISA’s combined reading literacy scale.

The study also found a student’s level of reading engagement was more highly correlated with their reading achievement than their socioeconomic status, gender, family structure, or time spent on homework. In fact, students with the lowest socioeconomic background but high reading engagement scored better than students with the highest socioeconomic background but low reading engagement.

Socioeconomic Status and Reading Performance

Overall, students with high reading engagement scored significantly above the international average on the combined reading literacy scale, regardless of their family background. The opposite was also true, with students with low reading engagement scoring significantly below the international average, no matter their socioeconomic status.

The authors suggested that reading practice can play an “important role” in closing achievement gaps between different socioeconomic groups. Frequent high-quality reading practice may help children compensate for—and even overcome—the challenges of being socially or economically disadvantaged, while a lack of reading practice may erase or potentially reverse the advantages of a more privileged background. In short, reading practice matters for kids from all walks of life.

For students within the United States, reading practice may not simply be more important than socioeconomic status—it may also be more important than many school factors.

Looking at only American students’ PISA scores, we see that reading engagement had a higher correlation with reading literacy achievement than time spent on homework, relationships with teachers, a sense of belonging, classroom environment, or even pressure to achieve (which had a negative correlation). In addition, a regression analysis showed achievement went up across all measures of reading literacy performance when reading engagement increased.

Correlation of Reading Engagement and Literacy Achievement

Although the PISA only assesses 15-year-olds, similar patterns can be seen in both younger and older American students. In 2013, the National Center for Education Statistics (NCES) compared students’ National Assessment of Educational Progress (NAEP) reading scores with their reading habits.4 For all age groups, they found a clear correlation between the frequency with which students read for fun and their average NAEP scores: The more frequently students read, the higher their scores were.

Reading Frequency and Reading Scores

What is especially interesting about the NAEP results is that the correlation between reading frequency and reading scores was true for all age groups and the score gaps increased across the years. Among 9-year-olds, there was only an 18-point difference between children who reported reading “never or hardly ever” and those who read “almost every day.” By age 13, the gap widened to 27 points. At age 17, it further increased to 30 points.

This seems to run contrary to the commonly held wisdom that reading practice is most important when children are learning how to read but less essential once fundamental reading skills have been acquired. Indeed, we might even hypothesize the opposite—that reading practice may grow more important as students move from grade to grade and encounter more challenging reading tasks. Until more research either confirms or disproves this possible explanation, it is nothing more than a guess, but an interesting one to consider nonetheless.

However, what is clear is that reading practice is decreasing among all age groups, with the most dramatic decreases among the very students who may need it the most.

Troubling declines in reading practice

Over the last three decades, reading rates have dramatically declined in the United States. In 1984, NAEP results showed the vast majority of 9-year-olds read for fun once or more per week, with more than half reporting reading almost every day. Only one in five reported reading two or fewer times per month. By 2012, 25% of all 9-year-olds were reading for pleasure fewer than 25 days per year.5

9-Year-Old Reading - 1984 vs 2012

For older students, the drop is even more precipitous. In 1984, 35% of 13-year-olds read for fun almost every day, and another 35% read one or two times per week—in total, more than two-thirds of 13-year-olds reported reading at least once a week. In 2012, nearly half read less than once a week.

13-Year-Old Reading 1984 vs 2012

Among 17-year-olds, the percentage reading almost every day dropped from 31% in 1984 to only 19% in 2012, while the percentage who read for fun less than once a week rose from 36% to 61%. The number of 17-year-olds reporting reading “never or hardly ever” actually tripled.

17-Year-Old Reading 1984 vs 2012

And the decline in reading is not due to students spending more time on homework in 2012 than in 1984. During the same time period, the percentage of students who reported spending more than an hour on homework actually declined.

In 1984, 19% of 9-year-olds, 38% of 13-year-olds, and 40% of 17-year-olds reported spending an hour or more on homework the day prior to the NAEP. In 2012, those numbers had dropped to 17% for 9-year-olds, 30% for 13-year-olds, and 36% for 17-year-olds.

Why are we seeing the greatest gaps and the greatest declines in the oldest students? Although many different factors are likely at play, one of them might be that the effects of reading practice are cumulative over a student’s schooling, especially when it comes to vocabulary.

The long-term effects of reading practice

What’s the difference between kids who read more than 30 minutes per day and those who read less than 15 minutes per day?

Twelve million.

Between kindergarten and twelfth grade, students with an average daily reading time of 30+ minutes are projected to encounter 13.7 million words. At graduation, their peers who averaged less than 15 minutes of reading per day are likely to be exposed to only 1.5 million words. The difference is more than 12 million words. Children in between, who read 15–29 minutes per day, will encounter an average of 5.7 million words—less than half of the high-reading group but nearly four times that of the low-reading group.1

Vocabulary Exposure and Daily Reading Time

Some researchers estimate students learn one new word of vocabulary for every thousand words read.6 Using this ratio, a student who reads only 1.5 million words would learn only 1,500 new vocabulary words from reading, while a student who reads 13.7 million words would learn 13,700 new vocabulary terms—more than nine times the amount of vocabulary growth.

This is especially important when we consider that students can learn far more words from reading than from direct instruction: Even an aggressive schedule of 20 new words taught each week will result in only 520 new words by the end of the typical 36-week school year. This does not mean that reading practice is “better” than direct instruction for building vocabulary—direction instruction is key, but teachers can only do so much of it. Instead, we ask educators to imagine the potential for vocabulary growth if direct instruction, structural analysis strategies, and reading practice are all used to reinforce one another.

Vocabulary plays a critical role in reading achievement. Research has shown that more than half the variance in students’ reading comprehension scores can be explained by the depth and breadth of their vocabulary knowledge—and these two vocabulary factors can even be used to predict a student’s reading performance.7

We can see the relationship between vocabulary and reading achievement clearly in NAEP scores, where the students who had the highest average vocabulary scores were the students performing in the top quarter (above the 75th percentile) of reading comprehension. Similarly, students with the lowest vocabulary scores were those who were in the bottom quarter (at or below the 25th percentile) in reading comprehension.8 This means those additional 12 million words could potentially have a huge impact on student success.

So what are we to do, when reading practice is so clearly connected to both vocabulary exposure and reading achievement, but not enough students are getting enough reading practice to drive substantial growth?

The answer seems clear. We need to make increasing reading practice a top priority for all students in all schools. Making reading practice a system-wide objective may be one of the most important things we can do for our students’ long-term outcomes, especially when we combine it with high-quality instruction and effective reading curricula. It is time to put as much focus on reading practice as we do on school culture, student-educator relationships, and socioeconomic factors.

However, not all reading practice is built the same. Quantity matters, but so does quality. In the next post in this series, we explore how you can ensure your students are getting the most out of every minute of reading practice.

To read the next post in this series, click the banner below.

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1 Renaissance Learning. (2016). What kids are reading: And how they grow. Wisconsin Rapids, WI: Author.
2 Renaissance Learning. (2015). The research foundation for Accelerated Reader 360. Wisconsin Rapids, WI: Author.
3 Kirsch, I., de Jong, J., Lafontaine, D., McQueen, J., Mendelovits, J., & Monseur, C. (2002). Reading for change: Performance and engagement across countries: Results from PISA 2000. Paris, France: Organization for Economic Co-operation and Development (OECD).
4 National Center for Education Statistics. (2013). The nation’s report card: Trends in academic progress 2012 (NCES 2013 456). Washington, DC: U.S. Department of Education Institute of Education Sciences.
5 National Center for Education Statistics. (2013). Table 221.30: Average National Assessment of Educational Progress (NAEP) reading scale score and percentage distribution of students, by age, amount of reading for school and for fun, and time spent on homework and watching TV/video: Selected years, 1984 through 2012. Digest of Education Statistics. Washington, DC: U.S. Department of Education Institute of Education Sciences. Retrieved from: https://nces.ed.gov/programs/digest/d15/tables/dt15_221.30.asp
6 Mason, J.M., Stahl, S. A. , Au, K. H. , & Herman, P. A. (2003). Reading: Children’s developing knowledge of words. In J. Flood, D. Lapp, J. R. Squire, & J. M. Jensen (Eds.), Handbook of research on teaching the English language arts (2nd ed., pp. 914-930). Mahwah, NJ: Lawrence Erlbaum Associates.
7 Qian, D. D. (2002). Investigating the Relationship Between Vocabulary Knowledge and Academic Reading Performance: An Assessment Perspective. Language Learning, 52(3), 513-536.
8 National Center for Education Statistics. (2013). 2013 Vocabulary report. 2013 Reading assessment. Washington, DC: U.S. Department of Education Institute of Education Sciences.