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 daily reading practice, reading growth, and overall student achievement.

Multiple studies show the connection between time and frequency of daily reading practice, reading growth, and reading test scores.

But students are reading less and less.

Explore the importance of daily reading practice in the Education Leader’s Guide to Reading Growth, a series about strategies for improving literacy achievement.

How reading 15 minutes a day leads to substantial gains in reading 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. We also examined 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 daily reading practice. A study of the reading practices of more than 9.9 million students 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 daily reading practice, 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 this 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.

Reading gains fall well below average when daily reading practice is less than 15 minutes

An analysis comparing the engaged daily reading practice and reading scores of more than 2.2 million students2 found that students who:

  • Read less than five minutes per day saw the lowest level of growth
  • Read 5–14 minutes a day saw sluggish gains that fell below national averages
  • Read 15 minutes or more a day saw accelerated reading gains higher than the national average
  • Read just over a half-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

… play a role in achievement, the consistent connection between time spent on daily reading practice and reading growth cannot be ignored.

Moreover, if daily reading practice is linked to reading growth and achievement, it follows that low levels of reading practice 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 daily reading practice and achievement

An analysis of more than 174,000 students’ Programme for International Student Assessment (PISA) scores revealed that the connection between daily reading practice 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 on daily reading practice, 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
  • 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 higher than the international average on the combined literacy scale, regardless of their family background.

The opposite was also true, with students with lower reading engagement scoring significantly below the international average, regardless of their socioeconomic status.

Closing achievement gaps with daily reading practice

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. But a lack of daily reading practice may erase or potentially reverse the advantages of a more privileged background.

In short, daily reading practice matters for kids from all walks of life.

Daily reading practice and PISA scores in the United States

For students within the United States, daily 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
  • Pressure to achieve (which has a negative correlation)

In addition, a regression analysis showed achievement went up across all measures of reading literacy performance when daily reading practice 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

NAEP results and the correlation between daily reading practice 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.

The differences between children who reported reading “never or hardly ever” and those who read “almost every day” were staggering:

  • Among 9-year-olds, there was an 18-point difference
  • 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 daily reading practice may grow more important as students move from grade to grade and encounter more challenging tasks.

Until more research either confirms or disproves this possible explanation, it is nothing more than a guess, but an interesting one to consider.

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

Troubling declines in daily 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 daily reading practice.

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 the 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. 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” 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, 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
  • 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 daily reading practice are cumulative over a student’s schooling—especially when it comes to vocabulary.

The long-term effects of daily 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.

Students with an average daily reading time of 30+ minutes between kindergarten and twelfth grade are projected to encounter 13.7 million words. At graduation, their peers who averaged less than 15 minutes of daily reading practice 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 vocabulary word 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. However, 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 per week will result in only 520 new words by the end of a typical 36-week school year.

This does not mean that reading practice is “better” than direct instruction for building vocabulary. Direct 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 daily reading practice are all used to reinforce one another.

The relationship between vocabulary and reading achievement

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 the NAEP scores. 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.This means those additional 12 million words could potentially have a huge impact on student success.

Making daily reading practice a priority for all students

So, what are we to do, when daily 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 daily reading practice a top priority for all students in all schools.

Making daily reading practice a system-wide objective may be one of the most important things we can do for our students’ long-term outcomes, especially if we combine daily reading with high-quality instruction and effective reading curricula.

It is time to put as much focus on daily 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 daily 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. 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.

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