The Power of Prior Knowledge: Helping Students Connect New Learning to What They Already Know
Learning never starts from scratch. Students bring experiences, language, ideas, memories, and knowledge into every lesson. What they already know can have a powerful influence on how well they understand and remember what they are learning next.
Learning Never Starts From Scratch
When students enter a classroom, they do not come with empty minds waiting to be filled with new information. They bring experiences, language, ideas, misconceptions, memories, and knowledge about the world. Everything they encounter in a new lesson is interpreted through what they already know.
That means one of the most important questions a teacher can ask before beginning instruction is not simply, “What am I going to teach today?” but also, “What do my students already know that will help them understand what I am about to teach?”
That is the power of prior knowledge.
What is Prior Knowledge?
Prior knowledge is the information, experiences, vocabulary, concepts, and understandings students already possess before encountering new learning.
When students learn something new, the brain does not simply store the information in isolation. New learning becomes more meaningful when students can connect it to knowledge that is already established in memory.
Imagine trying to hang a coat in a closet with no hooks. Without something to attach it to, the coat simply falls.
Prior knowledge provides the “hooks” that help students connect, organize, and make sense of new information.
This is why two students can listen to the same lesson, read the same passage, or watch the same demonstration—and come away with very different levels of understanding. They may have entered the lesson with very different knowledge.
Prior Knowledge Changes What Students Understand
Consider a class preparing to read a passage about coral reefs.
One student has visited a reef, watched documentaries about marine life, knows words such as coral, habitat, predator, and ecosystem, and understands that organisms depend upon one another for survival.
Another student has very little knowledge about oceans or marine life.
Both students may be able to read the words in the passage. But they are not approaching the text with the same resources for understanding it.
The first student has a network of knowledge to which the new information can attach. The second student is trying to build that network while simultaneously reading and understanding the passage.
That is much more demanding.
From the Classroom: When Good Readers Struggle to Understand
Years ago, I administered a reading screener to a class of sixth-grade students. I knew many of them to be good readers, so I was puzzled when a large number performed poorly on the comprehension questions.
The passage was about clouds.
At the time, I couldn't understand the results. These students could read the text—but many were struggling to answer questions about what they had read.
Later, I encountered research examining the role of background knowledge in reading comprehension. Suddenly, that experience with my sixth graders made much more sense.
I began to wonder whether some of those students simply lacked enough background knowledge about clouds to build a strong understanding of the passage. They could read the words, but reading the words was not necessarily enough to understand the ideas those words represented.
That experience stayed with me and reinforced an important lesson: When students can read the words but struggle to understand the text, we need to look beyond decoding and ask what knowledge they are bringing to the reading.
What the Baseball Study Taught Us
A classic study by Donna Recht and Lauren Leslie provides a powerful illustration of the role background knowledge can play in reading comprehension.
The researchers studied junior-high students who differed in both reading ability and their knowledge of baseball. Students read a passage describing part of a baseball game and were then asked to demonstrate and recall what they had understood.
The results were striking. Students' knowledge of baseball had a powerful influence on how well they understood and remembered the passage. Students with greater knowledge of the topic were able to use that knowledge to help make sense of what they were reading.
The study does not mean that reading ability is unimportant. Rather, it demonstrates that comprehension depends on more than being able to read the words accurately. Readers also bring their knowledge of the topic to the text.
This helps us understand why two students with similar reading skills may comprehend the same passage very differently—and why a strong reader may sometimes struggle with a text about an unfamiliar topic.
Sometimes what looks like a comprehension problem may actually be, at least in part, a knowledge problem.
Activating Prior Knowledge Is Not the Same as Building It
Teachers are often encouraged to activate prior knowledge before beginning a lesson. That is good instructional practice—but there is an important distinction.
We can only activate knowledge that is already there.
Sometimes students simply do not have enough relevant knowledge to activate.
In those situations, asking, “What do you already know about coral reefs?” may produce very little useful information. The teacher may need to build background knowledge first.
That might mean briefly showing a photograph or diagram, explaining several important concepts, introducing essential vocabulary, connecting the topic to a familiar experience, reading a short introductory passage, or demonstrating something students have never encountered.
The goal is not to spend half the lesson “activating prior knowledge.” The goal is to make sure students have enough of a foundation to understand what comes next.
TRY THIS TOMORROW
Try this simple Connect–Check–Build Routine before introducing new learning. It can take just a few minutes.
CONNECT — What does this remind you of?
Help students retrieve something relevant they have previously learned or experienced.
CHECK — What do we already understand?
Ask a few carefully chosen questions. Listen for both accurate knowledge and misconceptions.
BUILD — What do we need to know before we begin?
Briefly teach any essential vocabulary, concepts, or background information students are missing.
The goal: Give new learning somewhere to connect.
When Prior Knowledge is Incorrect
There is another challenge. Sometimes students already know something about the topic—but what they “know” is incorrect.
A child may believe that all animals that live in water are fish. A student may think multiplication always makes numbers larger. Another may believe that seasons occur because Earth moves closer to or farther away from the sun.
These misconceptions can interfere with new learning.
Effective teachers therefore do more than ask students what they know. They listen carefully to what students think they know. Misconceptions need to be uncovered and addressed explicitly so that new learning is not simply added on top of an incorrect understanding.
What This Means For Teachers
Before beginning a new lesson, consider three questions:
1. What do students need to already know?
Identify the essential concepts, vocabulary, experiences, or skills students will need in order to understand the new learning.
2. Do my students actually know it?
Don't assume. Ask a few carefully chosen questions, use a quick review, or give students an opportunity to explain what they already understand.
3. What should I do if they don't?
Build the missing knowledge before moving on. A photograph, diagram, brief explanation, example, short video, demonstration, or vocabulary discussion may provide the foundation students need.
Sometimes two or three minutes of carefully chosen explanation can prevent twenty minutes of confusion later.
This Matters in Every Classroom
This principle applies across the curriculum. Whether students are learning fractions in mathematics, ecosystems in science, a new period in history, or interpreting a story in English language arts, new learning depends in part on what they already know.
When prerequisite knowledge is missing, teachers may need to build that foundation before moving forward.
Sometimes a few minutes spent establishing essential knowledge at the beginning of a lesson can prevent much more confusion later.
Prior Knowledge and Reading Comprehension
Prior knowledge becomes especially important when students read. Reading comprehension requires more than accurately recognizing the words on a page.
Readers must connect ideas across sentences, understand vocabulary, make inferences, recognize relationships, and integrate information from the text with what they already know.
This helps explain something teachers sometimes find puzzling: A student can read a passage fluently and still understand very little of it.
The difficulty may not always be decoding. Sometimes the student simply does not possess enough knowledge of the topic or the language used to discuss it.
This is one reason building knowledge and vocabulary across subjects—science, social studies, literature, the arts, and the wider world—is an important part of developing strong readers.
Research Behind This Resource
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.
Shanahan, T., Callison, K., Carriere, C., Duke, N. K., Pearson, P. D., Schatschneider, C., & Torgesen, J. (2010). Improving Reading Comprehension in Kindergarten Through 3rd Grade: A Practice Guide (NCEE 2010-4038). National Center for Education Evaluation and Regional Assistance, Institute of Education Sciences, U.S. Department of Education.
Foorman, B., Beyler, N., Borradaile, K., Coyne, M., Denton, C. A., Dimino, J., et al. (2016; revised 2019). Foundational Skills to Support Reading for Understanding in Kindergarten Through 3rd Grade. Institute of Education Sciences, U.S. Department of Education.
Willingham, D. T. (2006). How knowledge helps: It speeds and strengthens reading comprehension, learning—and thinking. American Educator, 30(1), 30–37.
Center for Reading and Dyslexia
Translating research into classroom practice.