Structured Literacy, Science of Reading: What’s the Difference?

I was moved to write this post after recently reading and listening to several resources in which Reid Lyon figures prominently, including a new article titled Clarifying Structured Literacy: Moving the Conversation Forward, authored by Lyon with colleagues Timothy Odegard and Megan Gierka. In this piece, the authors explain that terms such as the Science of Reading and Structured Literacy have entered public discourse and policy legislation over the past few years. However, they argue that a lack of shared understanding of what these terms mean has contributed to confusion in both policy and practice, noting that “shared terminology is often adopted more quickly than shared understanding.”

Reid Lyon: Contributions to the Field

Reid Lyon is a neuroscientist who led the Child Development and Behavior Branch within the National Institute of Child Health and Human Development from 1992 until 2005. He was the force behind some of the most important scientific studies on reading across several decades, and played a key role in the development of both the National Reading Panel and the Reading First legislation. His work has had a significant impact on me personally, beginning with my early encounters with reading research in the early to mid-2000s, when I served as one of the lead trainers in Massachusetts for the Reading First initiative. Lyon has since come out of retirement to help champion renewed efforts to improve literacy instruction

A few months ago, I had the opportunity to hear Lyon speak at a national literacy conference, where he raised concerns about the persistent use of imprecise language in the field. During his presentation, he reflected on his work in the early 2000s and noted that, when sharing research findings, he and his colleagues could have done a better job clarifying the findings themselves, the associated related terminology, and the implications for classroom practice.

Lyon addresses the lack of precise operational definitions for essential concepts and critiques oversimplified contrasts in literacy debates that obscure details critical to improving reading outcomes. In a recent piece titled If At First You Don’t Succeed… Definitely Don’t Do It Exactly the Same Way Again—Unless You Are Involved in Reading Education he offers examples of familiar dichotomies—such as phonics versus balanced literacy, social versus emotional development, quantitative versus qualitative research—and notes that positions framed in these binary terms often rest more on preference or ideology than on evidence. As Lyon explains:

“One core problem underlying today’s debates about the Science of Reading and Structured Literacy is our longstanding inability to define our terms. We do not communicate with precision. We fail to agree on operational definitions for essential concepts. As a result, we remain ineffective at developing a shared and stable professional knowledge base. This should not be surprising— learning to read is a complex process requiring the coordinated development of multiple component skills. What is surprising is how persistently we rely on imprecise language and vague generalities to explain the complexity of reading development, reading difficulties, and reading instruction.”

He further points out that today’s debates over the Science of reading and Structured Literacy continue this pattern:

“The conversation is often emotional, frequently imprecise, and rarely focused on the specific implementation errors that derail the application of robust scientific findings in real classrooms.  The conversation also fails to create solutions.  For those who have watched reading education evolve across several decades, this terrain is familiar: different labels, same misunderstandings.”

What is the Science of Reading?

Although research on effective reading instruction has existed for decades, the term Science of Reading, used to describe this body of research, has gained prominence in recent years. Science of Reading refers to a comprehensive and evolving body of scientific knowledge drawn from education, cognitive psychology, developmental psychology, and neuroscience. This research explains how individuals learn how to read, why some struggle, and how reading can be taught most effectively. Research related to writing is also included within the Science of Reading.

This body of research spans more than five decades and continues to grow as new evidence emerges. It is important for educators to understand that the Science of Reading is not a curriculum, program, or a single component of literacy instruction (such as phonics or comprehension). Rather, it represents the accumulated scientific evidence base that informs effective literacy instruction.

What is Structured Literacy?

In 2021, I wrote a blog post titled What is Structured Literacy Instruction?, which focused on the effectiveness of Structured Literacy for teaching students with dyslexia. In that post, I shared information from the International Dyslexia Association, along with a link to a video from the Center for Dyslexia at Middle Tennessee State University. I also emphasized that explicit instruction across all components of reading and writing is a hallmark of Structured Literacy.

The recent article by Lyon, Odegard, and Gierka clarifies that Structured Literacy is intended for all students, not only those who struggle with reading. They define it as follows:

“Structured Literacy refers to an approach to literacy instruction that specifies both the content of instruction and the principles by which that content is taught. It is grounded in converging evidence from the Science of Reading, but it is not itself a theory of reading development, nor is it synonymous with the Science of Reading. Rather, Structured Literacy represents a translation of that science into instructional practice by articulating what is taught and how instruction and practice are organized to support learning.”

The authors explain that Structured Literacy “encompasses language and literacy at multiple levels, including phonological awareness, sound–symbol correspondences, orthographic patterns, morphology, syntax, semantics, and discourse. Importantly, this scope extends beyond word reading to include spelling, reading comprehension, and written expression.”

Explicit Instruction

Lyon, Odegard, and Gierka emphasize that the instructional principles guiding how reading and writing are taught are also central to Structured Literacy, particularly the use of explicit, systematic instruction. As they explain:

“A defining feature of Structured Literacy is its emphasis on structure informed by the inherent organization of oral and written language. Language is not arbitrary, but patterned at multiple levels, including sounds and symbols, words, sentences, and extended texts. Structured Literacy rests on the premise that learners cannot be expected to reliably infer these underlying patterns through exposure alone. For this reason, supporting proficiency in reading and written expression is most effective when the structure of language and its representation in print are made explicit and visible to learners.”

For those interested in hearing more directly from Reid Lyon, a recent podcast titled Emily Hanford LIVE from Planet Word with Reid Lyon and Margaret Goldberg is available. In the interview, Lyon explains:

“Explicit instruction is leaving nothing to chance. Don’t leave anything to chance. Even if you think some things will be picked up automatically, everything needs to be pinpointed for the youngster, well-defined — what you’d like the child to do, the kind of responses that you would like the child to indicate what they’re learning. Again, it’s kind of common sense.”

(See also my 2025 post Principles of Effective Literacy Instruction and my 2022 post What Is Direct, Systematic and Explicit Instruction?)

The Who, the What, the How, and the Why

The International Dyslexia Association offers a free infographic titled Structured Literacy: An Approach Grounded in the Science of Reading which provides a concise summary of the following:

• Who uses Structured Literacy: General education teachers providing Tier I core instruction, as well as general and special education teachers, reading specialists and intervention staff providing Tier 2 or 3 supplemental and intensive support.
• What is taught: Word recognition and comprehension for reading; handwriting, spelling, and composition for writing.
• How to teach: Through a direct and systematic approach that is explicit, sequential, cumulative, and data-driven.

The infographic identifies the Science of Reading as the why—the scientific evidence from accumulated research on reading and writing acquisition that underpins the content and instructional principles of structured literacy.

What Structured Literacy Is Not

One aspect I particularly appreciate about the Lyon, Odegard, and Gierka article is the clarity with which it explains what Structured Literacy is not. The authors make several key points:

• It is neither based in ideology nor politically motivated. “Its strength lies in its scientific foundation and its openness to ongoing evaluation and revision. As new research findings emerge, refinements to its instructional content and principles are expected.”
• It is not a program. “Programs may be aligned with Structured Literacy principles to varying degree, but no single curriculum or scope-and-sequence defines Structured Literacy.”
• It is not limited to early phonics instruction. “While explicit, systematic teaching of foundational word-reading skills is essential, it does not constitute the full scope of Structured Literacy. From its earliest inception, Structured Literacy has included spelling as a core component of written language instruction, along with sentence- and text-level language and writing. Narrowing the approach to phonics alone represents an incomplete understanding of the framework.”
• It includes comprehension instruction. Structured Literacy “does not reduce comprehension to background knowledge alone. Research in reading comprehension has consistently demonstrated that understanding written language depends on multiple interacting processes, including accurate word recognition, language comprehension, vocabulary, syntax, text structure, and strategic engagement with text. Importantly, these strategic and regulatory processes do not reliably develop simply as a byproduct of decoding proficiency and accumulated knowledge.” (See my 2024 post In Support of Main Idea and Comprehension Strategy Instruction.)
• It includes explicit writing instruction. “Students must be taught how to generate, organize, and communicate ideas in writing, including strategies for sentence construction, cohesion, and revision.” (See my 2023 post Stages of the Writing Process, and my 2022 post New Book: The Writing Rope)

Why There Is Confusion About Structured Literacy

The Lyon, Odegard and Gierka article concludes by highlighting three areas where the scope and intent of Structured Literacy are often constrained in practice:

• Limited scope of instructional targets: Structured Literacy is often misinterpreted as primarily foundational phonics instruction.
• Insufficient practice and application for proficiency: Students may receive limited opportunities to apply what they are learning through sustained reading and writing. Instruction must be supported by structured practice that provides sufficient time, repetition, and application in meaningful contexts.
• Limited use of data to differentiate instruction: Structured Literacy relies on ongoing, instructionally relevant formative assessment to guide instructional decisions. However, many educators struggle to use data in ways that allow instruction to be responsive to individual student needs. (See my 2024 post Reading Assessment Model, Grades 5-12 and my 2022 post Reading Assessment Basics.)

ADDITIONAL RESOURCES

• (Website) The Science of Reading: An Overview. National Center on Improving Literacy.
• (Guide) The Science of Reading Defining Guide. The Reading League, 2021.
• (Webinar) Misunderstanding of the Science of Reading, Sharon Vaughn, Webinar, April 10, 2024
• (Infographic) Structured Literacy: An Approach Grounded in the Science of Reading. International Dyslexia Association.
• (Journal) Perspectives, 75th Anniversary Issue: Structured Literacy Grounded in the Science of Reading. Winter 2024, Volume 50, No. 1.