Anyone who鈥檚 ever scratched their head over their car manual or struggled to parse a website鈥檚 terms of service knows: It鈥檚 hard to read about a topic you don鈥檛 really understand.
It鈥檚 a common-sense statement that鈥檚 backed by research. Studies have shown that readers use their background knowledge鈥攙ocabulary, facts, and conceptual understanding鈥攖o comprehend the text they read.
Much of this evidence isn鈥檛 new. But it鈥檚 received more attention now, amid the 鈥渟cience of reading鈥� movement.
In recent years, a growing number of parents, teachers, and reading researchers have called for changes to early literacy instruction, to bring it more in line with the evidence base around how children learn to read. Often, schools weren鈥檛 taking research-based approaches to teaching students a crucial building block of reading鈥攈ow to sound out words. If kids can鈥檛 get the words off the page, they can鈥檛 extract meaning from text.
Over the past three years, about two dozen states have passed laws mandating that students are taught these skills in an explicit, systematic way.
Over the past few years, more states have passed laws or implemented new policies related to evidence-based reading instruction. Look below to see which states have such legislation and when it passed.
Click here to learn more about each state鈥檚 legislation or policy.
At the same time, though, some science of reading advocates have said that foundational skills instruction isn鈥檛 the only piece of literacy learning that needs an overhaul. They argue that schools also don鈥檛 do enough to support students鈥� background knowledge鈥攁 key factor in their understanding of any text. That鈥檚 the issue explored in The Knowledge Gap, a book that鈥檚 made its way onto district leaders鈥� reading lists and into teacher professional learning groups.
Over the past few decades, reading comprehension instruction has become 鈥渃ontent agnostic,鈥� focused on skill practice, to the detriment of learning about science, history, and other disciplines, said Sonia Cabell, an associate professor at Florida State University鈥檚 College of Education.
鈥淚n the No Child Left Behind era, and the Reading First era, reading became the main focus. Reading blocks were lengthened. This pushed out the science and social studies instruction,鈥� Cabell said, referring to the 2002 federal law and a $1 billion-a-year reading program it created.
Cabell and other researchers who study the integration of content knowledge and literacy instruction say the focus on 鈥渒nowledge building鈥� holds promise. But they also say there are a lot of unanswered questions about how these approaches should be designed, and how much they can actually improve reading achievement.
Here鈥檚 what experts and research say about what a greater focus on content knowledge could mean for reading instruction.
What role does background knowledge play in reading comprehension?
A big one. Decades of studies have shown that children can understand text better if they have some background knowledge about the topic. (See for a recent review of the research.)
This may seem like an obvious finding: Of course, kids can understand a book or an article better if they already know a bit of what it鈥檚 about. It鈥檚 likely easier to read a text about paleontologists, for example, if you already know the words 鈥渇ossil鈥� and 鈥渆xtinction,鈥� and you know that animal species that used to exist have since died out.
This applies even for children who are otherwise poor readers. One example of this is what鈥檚 often referred to as 鈥渢he baseball study.鈥�
In , researchers Donna Recht and Lauren Leslie divided middle schoolers up into groups, based on two factors: their general reading ability, and their knowledge about baseball. Then they asked the kids to read a passage about a game.
They found that the baseball lovers who scored low on a general reading test could understand and recall the text better than the higher-scoring kids who didn鈥檛 know as much about the game.
So, background knowledge about a specific topic is helpful in understanding text on that topic. But what about in general? Does knowing more about the world lead to better reading comprehension overall?
A large body of research shows a correlation: Children who score higher on tests of general knowledge are better readers. These kids also tend to grow more than their peers in reading comprehension over time, said Gina Cervetti, an associate professor at the University of Michigan鈥檚 School of Education, who studies the connections between literacy and content-area learning.
But other factors could play a role, too.
鈥淭hose kinds of correlations are tricky, because there are a lot of other things that are going on,鈥� said Timothy Shanahan, an emeritus professor of education at the University of Illinois Chicago. People who score higher on tests of general knowledge also tend to have greater language ability, and tend to be from higher-income backgrounds.
If background knowledge is linked to reading ability, does teaching knowledge help kids become better readers?
It can. But there are some caveats.
There are a few different ways that teachers can connect content knowledge and literacy instruction in the elementary school day. One option is to merge the two鈥攖o embed literacy instruction into social studies and science, teaching students cognitive strategies to help them engage with the content.
This has positive results. In a , researchers HyeJin Hwang, Sonia Cabell, and Rachel Joyner examined studies that took this integrated approach to literacy and content-area instruction. Kids who were taught this way retained more vocabulary and understood content better than children who learned science or social studies separately from reading instruction.
These students also did better on standardized tests of reading comprehension. The integrated approach not only made them better readers of the content they were learning, it made them better readers overall.
These programs weren鈥檛 teaching kids ... knowledge as a set of facts to be learned. These kids were learning deeply about a set of concepts.鈥�
Another approach is to build it into reading classes, developing English/language arts units that are structured to deepen students鈥� understanding about different topics. This is often the approach advocates are referencing when they promote high-quality or 鈥渃ontent-rich鈥� curriculum.
This method has shown more mixed results.
Most studies of this approach find that it has a positive effect on students鈥� knowledge of the subject in question鈥攆or example, teaching a 4th grader about the American Revolution will likely mean that they know more about the American Revolution. But only lead to higher scores on tests of general reading comprehension.
One that does is the Model of Reading Engagement, or MORE. It was developed by Harvard education professor James Kim and his colleagues.
The approach aims to build students鈥� science content knowledge through literacy lessons. But it鈥檚 not just focused on acquiring facts. The researchers designed the lessons with the goal of helping kids to build a schema鈥攁 mental model that they could then apply to understand new, related concepts.
The overarching theme of the program, in this case, was how scientists study past events. Throughout 1st and 2nd grade, students learned about interrelated concepts that would build that schema. Units centered on how animals survive in their habitats, and how paleontologists study prehistoric animals and events. A from Kim and his colleagues found that the approach helped students apply the science vocabulary and concepts they learned to other contexts.
Kim鈥檚 study, and others that have shown general effects on reading comprehension, hold something in common, said Cervetti.
鈥淭hese programs weren鈥檛 teaching kids a bunch of knowledge at a superficial level. It wasn鈥檛 knowledge as a set of facts to be learned,鈥� she said. 鈥淭hese kids were learning deeply about a set of concepts.鈥�
Still, in Kim鈥檚 study, there was a limit to how far kids could transfer the knowledge that they learned. Generally, the new texts had to include explicit connections to the words and concepts they鈥檇 learned. If the familiar concepts were missing, students couldn鈥檛 make the connections themselves.
If kids can鈥檛 make connections between related topics, 鈥渋t鈥檚 a signal to teachers of what they need to go back and discuss,鈥� Kim said.
How should schools decide what kids should read and write about? What knowledge should be the focus?
This question has dogged the American education system for decades鈥攊f not centuries.
It鈥檚 the debate at the heart of many decisions about teaching and learning. The conversation is particularly volatile now, as parents鈥� groups and Republican legislators seek to limit what students can read and discuss in the classroom.
Studies鈥� insight on this topic is limited. Evidence would suggest that students鈥� curiosity should play a role, Cervetti said. There鈥檚 a large body of work demonstrating that student interest and motivation have a strong impact on academic achievement.
But outside of that, things are more fuzzy. What鈥檚 the right balance of depth versus breadth in topics? What knowledge will best prepare students for their lives outside of school? Researchers don鈥檛 know.
Still, some education scholars have offered prescriptions. Perhaps the most well-known鈥攁nd certainly one of the most debated鈥攐f these roadmaps was developed by E. D. Hirsch Jr., a professor emeritus of education and humanities at the University of Virginia and the modern father of the knowledge-building movement.
Hirsch popularized the idea that students needed to learn about something in order to read well. In his 1987 book Cultural Literacy: What Every American Needs to Know, Hirsch outlined a list of essential figures, events, and concepts. He tried to identify the background knowledge that would comprise a sort of cultural canon鈥攖he information that most writers and speakers would assume their audience shared.
Its contents provided the framework for Core Knowledge Language Arts, an ELA curriculum. But Hirsch鈥檚 work also saw a swift and strong backlash from critics who said his list was Eurocentric and elitist.
Hirsch has argued that the approach he advocates is a way of providing equal opportunity, putting children on an even playing field with a shared reserve of knowledge鈥攔egardless of their cultural, racial, or socioeconomic backgrounds.
Still, the question of whose knowledge matters鈥攚hat鈥檚 important for children to know and who gets to decide鈥攊s far from settled.
Some more recent efforts have used Hirsch as inspiration. The Johns Hopkins Institute for Education Policy has created , tools it uses in work with districts looking to evaluate how and where their curricula build knowledge.
The Knowledge Maps are based on Hirsch鈥檚 core knowledge guidelines with some additions and changes鈥攕uch as added criteria around diversity, equity, and inclusion, said Ashley Berner, the director of the institute.
Other programs have taken different approaches. In the MORE intervention, Kim and his co-authors tried to choose content that was 鈥渢imely and timeless.鈥� Timely, in that it aligned to current state standards in science. And timeless: It has shown up consistently in state standards over the past two decades, and science professors think that it鈥檚 relevant and accurate.
Of course, these are still subjective decisions鈥攁n inevitability in choosing knowledge, said Shanahan. 鈥淲hen it comes to certain aspects of the arts, and science, and social studies, what content do we want kids to know? Those are value judgments,鈥� he said.
Is knowledge the only factor in reading comprehension ability?
Far from it. Children don鈥檛 just need to learn information. They also need to know how to organize it in their minds, use it, and apply it in new contexts.
Teaching comprehension strategies can help students become skilled at these tasks. that explicitly teaching students how to use these strategies鈥攍ike summarizing, visualizing, creating graphic organizers, and asking questions about their understanding鈥攎akes them better readers.
Teaching students about how different types of text are structured has also been shown to improve reading comprehension.
鈥淭his is a clear case in our field of a 鈥榖oth-and,鈥� not an 鈥榚ither or,鈥� said Nell Duke, the executive director of the Center for Early Literacy Success at Stand for Children.
In fact, most of the knowledge-building interventions that show positive effects in the research literature have combined content-area instruction with these kinds of strategies for metacognition, said Cervetti.
Cervetti thinks it鈥檚 likely that deep content area knowledge and students鈥� ability to use comprehension strategies reinforce each other.
鈥淚magine being a kid who has read lots of texts, but every text you encounter is unfamiliar ideas and unfamiliar words,鈥� she said. 鈥淵ou get through the text and you walk away having understood something about that text. But probably not enough to be a better comprehender.鈥�
With these topically disconnected texts, the student doesn鈥檛 have the chance to practice the strategies that good readers use, Cervetti said, like making connections or asking questions prompted by prior knowledge. But if the texts work together to build a bigger conceptual understanding, they do present those opportunities. Knowledge, she hypothesized, 鈥渂uilds momentum鈥� for kids to practice the comprehension strategies that research shows are powerful tools.
There鈥檚 also some evidence that knowledge-rich contexts naturally facilitate richer conversations. A by Cabell and her colleagues found that preschool teachers used more sophisticated language structures when they integrated reading and science instruction.
What do all of these findings mean for classroom practice?
The main takeaway is that reading instruction should be engaging students in deep, substantive ideas, said Cervetti.
Yes, learning about something鈥攈aving clearly defined topics鈥攊s important. But these topics need to help students build a broader, conceptual understanding.
That means that instead of learning about 鈥渙ceans鈥濃�攁n umbrella that could encompass everything from reading news articles about microplastics to studying Moby Dick鈥攁 unit might be centered around a theme, such as, 鈥渨e have one connected water system.鈥�
Some English/language arts curricula attempt to structure units this way, developing them around social studies and science ideas. But Duke cautioned that these ELA programs shouldn鈥檛 be seen as a substitute for instruction in other subject areas.
Science and social studies don鈥檛 just teach content; they also teach discipline-specific practices鈥攍ike developing a hypothesis or analyzing a primary source. 鈥淭hat kind of information, in my perception, doesn鈥檛 tend to make it into ELA curricula,鈥� she said.
鈥淚 think an increasing segment of the field is picking up on the idea that content-rich English/language arts instruction is better for kids,鈥� Duke added. 鈥淏ut it has not fully tackled the question of, when in our day is there space left for science and social studies? And [there鈥檚] little attention to, how do we coordinate that across the school day?鈥�
