Why Background Knowledge Is the Missing Link in Reading Fluency and Comprehension

Part 1: Background Knowledge

By Karla O’Brien

If you haven’t had a chance to read the original post, Crossing The Bridge to Reading Fluency, I’d encourage you to start there, as it lays the foundation for everything we’ll be building on in this series.

This post is the first in a series where I’ll be unpacking what I think of as the main supports on the bridge of reading fluency. Each part will take a closer look at one of the elements that helps move our students from accurate decoding to truly meaningful, fluent reading.

Because if there’s one thing I’ve learned in the classroom, it’s this: fluency doesn’t develop from a single skill. It’s built and supported by multiple pieces working together, and when one of those pieces is missing, we see it in our students right away.

One of the most overlooked, and most powerful, of those supports is background knowledge.

What Happens When Readers Lack Background Knowledge?

Let me start with something I’ve actually done with my own students, and with teachers during training sessions.

I present them a passage similar to this:

Begin by securing the zelphic coil within the outer chamber. Once stabilized, rotate the axial lever until the harmonic gauge reaches a balanced state. Next, introduce a measured pulse through the primary conduit to initiate alignment. If calibrated correctly, the system will produce a steady oscillation indicating successful synchronization.

Then I ask them, honestly, “How did that feel to read?”

Most people pause. Some laugh a little. And almost everyone says some version of the same thing: “I could read the words… but I had no idea what I just read.”

And that’s the moment I want to sit in for a second.

Because typically, these are strong readers. They didn’t struggle to decode zelphic or oscillation. But their reading wasn’t smooth. It wasn’t expressive. And it certainly wasn’t meaningful. You could almost feel the cognitive load building as they tried to make sense of something that just didn’t connect to anything they already knew.

Then I give them something familiar like this:

First, take two slices of bread and lay them flat on a plate. Use a knife to spread peanut butter on one slice. Then, spread jelly on the other slice. Carefully press the two slices together so the spreads are on the inside. Finally, cut the sandwich in half and enjoy.

Why Background Knowledge Changes the Reading Experience

And just like that, everything changes.

The reading feels easier, faster, and smoother. There is expression and confidence. When you ask for a retell, there is no hesitation because they can clearly picture what is happening as they read.

The sentences are similar in length and structure, yet the experience is completely different.

Why?

Because of background knowledge.

This is something I saw play out in my classroom all the time. When students already knew something about a topic, everything about their reading would shift. They could move through the text with more ease. They could anticipate what was coming next. Their phrasing improved. Their comprehension deepened, almost automatically, and they could create a vivid mental movie.

But when that knowledge wasn’t there, even capable readers would start to slow down. They would lose the thread of meaning. And often, we misinterpret that as a reading issue, when it’s really a knowledge issue.

What the Research Says About Background Knowledge and Comprehension

This idea isn’t just anecdotal, it’s backed by research. One of the most powerful studies that illustrates this comes from the well-known Baseball Study by Donna Recht and Lauren Leslie (1988). They wanted to understand what matters more when it comes to comprehension: general reading ability or knowledge about the topic.

The Baseball Study and What It Reveals About Reading and Knowledge

They worked with middle school students and grouped them by reading ability and by how much they knew about baseball. All students read a passage describing part of a baseball game. After reading, they reenacted the game using a model field, retold what happened, and created summaries.

The findings are something every teacher should hear.

Students who knew more about baseball performed better regardless of their reading level. In fact, students considered lower readers but with strong background knowledge often outperformed higher readers who lacked that knowledge. Their retellings were more accurate, their summaries were more organized, and their understanding was deeper.

In other words, knowledge didn’t just help, it leveled the playing field. (No pun intended!)

Background Knowledge in Structured Literacy and Dyslexia Instruction

In structured literacy approaches, including Orton-Gillingham-based instruction, we often focus heavily on decoding, but background knowledge plays an equally important role in comprehension.

I think about that often when I’m working with students who are struggling. It forces me to pause and ask: Is this really a decoding issue? Or is this a knowledge gap?

Because if a student doesn’t have a framework to attach new information to, reading becomes incredibly taxing. This connects directly to what we know from cognitive science. Our working memory can only hold so much at once. When students are trying to decode, figure out vocabulary, and build meaning without any prior knowledge, that system gets overwhelmed quickly (Sweller, 1988). We see the impact of that overload in their fluency.

We often define fluency as accuracy, rate, and prosody, but in practice, all three are deeply tied to meaning. When a student understands what they’re reading, their pace naturally improves, their expression reflects the text, and their reading sounds like language, not just word calling.

But when meaning breaks down, the reading becomes choppy, expression flattens, and comprehension slips further out of reach (Kuhn & Stahl, 2003).

This is why I think of background knowledge as a critical support on the bridge to fluent reading. Decoding gets students onto the bridge, but knowledge is what helps them move across it with confidence and ease.

What This Means for Instruction in the Classroom

It means we cannot assume students are bringing the knowledge they need. We have to build it intentionally.

Building Background Knowledge Before and During Reading

Sometimes that looks like taking a few minutes before reading to introduce key ideas or vocabulary in a way that sticks. Sometimes it means providing rich, interactive read-alouds of more complex texts, where we pause to connect ideas, discuss meaning, and model thinking aloud. These read-alouds give students access to ideas and language that might be beyond their independent reading level, while giving them repeated opportunities to hear and think through new concepts. When we stay on a topic across multiple texts and provide repeated exposure to the same concepts, their understanding and language grow much more quickly.

The Role of Discussion, Re-Reading, and Text Sets

It also means giving students space to talk, because when they can explain ideas, make connections, and hear how others are thinking, their knowledge begins to solidify, and when we revisit texts, reading them more than once with a clearer understanding each time, we strengthen both comprehension and fluency together.

None of these practices are new, but when we view them through the lens of knowledge-building, they become more intentional.

The Bridge to Reading Fluency Starts with Knowledge

Even though much of our work focuses on dyslexia, the truth is that students are not always struggling because they cannot read the words. Sometimes they are struggling because they do not yet know enough to make sense of what they are reading.

When we start there, and build knowledge alongside skills, we do more than improve comprehension. We change the entire reading experience.

By Karla O’Brien

References

Beck, I. L., McKeown, M. G., & Kucan, L. (2013). Bringing words to life: Robust vocabulary instruction (2nd ed.). Guilford Press.

Graves, M. F. (2006). The vocabulary book: Learning and instruction. Teachers College Press.

Hirsch, E. D. (2006). The knowledge deficit: Closing the shocking education gap for American children. Houghton Mifflin.

Kuhn, M. R., & Stahl, S. A. (2003). Fluency: A review of developmental and remedial practices. Journal of Educational Psychology, 95(1), 3–21.

Recht, D. R., & Leslie, L. (1988). Effect of prior knowledge on good and poor readers’ memory of text. Journal of Educational Psychology, 80(1), 16–20.

Samuels, S. J. (1979). The method of repeated readings. The Reading Teacher, 32(4), 403–408.

Shanahan, T., & Shanahan, C. (2008). Teaching disciplinary literacy. Harvard Educational Review, 78(1), 40–59.

Snow, C. E. (2002). Reading for understanding: Toward a research and development program in reading comprehension. RAND.

Sweller, J. (1988). Cognitive load during problem solving: Effects on learning. Cognitive Science, 12(2), 257–285.