Aligning Writing Instruction with Cognitive Science

What can cognitive science tell us about how to unlock the benefits of writing? The evidence suggests three basic principles.

First, we need to ensure that writing activities are embedded in the content of the curriculum as much as possible. That not only provides students with the knowledge they need in order to write coherently but also reinforces the knowledge we want them to retain. When students recall information they may have slightly forgotten in order to write about it, they engage in what cognitive scientists call “retrieval practice.” The more you practice retrieving an item of information from long-term memory, the more likely you are to be able to recall it when you need it in the future. The ability to connect new information to prior knowledge is crucial to learning.

Second, we need to teach grammar and conventions in the context of students’ own writing. Studies have shown that teaching conventions and rules for writing in the abstract doesn’t help most students, yet they also show that many students don’t absorb those things naturally. What works best is to have students focus on the practical application of grammatical concepts. Generally, it makes sense to highlight sentence structures that are common in writing but not in speech. The idea is to teach grammar not for its own sake but with an eye to what will be most useful for producing and understanding complex text. For example, it might not be necessary to teach students what a prepositional phrase is, since they use them all the time when speaking. 

One grammatical concept worth teaching is the appositive—a phrase that describes a noun. Learning to use appositives, along with other structures that appear frequently in written language, will not only improve students’ writing but also boost their reading comprehension. Students unfamiliar with appositives can be confused by a sentence such as “Rachel Carson, a scientist, writer, and ecologist, grew up in the rural river town of Springdale, Pennsylvania.” Many might assume the sentence refers to four different people who all grew up together. 

An activity called sentence combining, which has been found to improve students’ writing, can be used to help familiarize students with appositives. It involves giving students two, three, or more simple sentences and having them combine them into one longer, more complex sentence.

For example, a teacher could first teach students about appositives and then give them the following sentences:

• Rachel Carson grew up in the rural river town of Springdale, Pennsylvania.
• Rachel Carson was a scientist.
• Rachel Carson was a writer.
• Rachel Carson was an ecologist.

Students might then come up with a complex sentence that uses an appositive to describe Rachel Carson.

The third principle requires us to modulate the heavy cognitive load that writing imposes so that students have the cognitive capacity to use writing as a lever for learning—and to learn to write well. “Cognitive load” refers to the burden that a task places on working memory, which can only juggle about five items of new information for about 20 seconds. If the cognitive load is too heavy, then our ability to learn disappears.

One way to modulate cognitive load is through what cognitive scientists call deliberate practice. That term applies to acquiring any complex skill, such as playing tennis or the violin—or writing. Although writing is heavily reliant on knowledge, it also involves skills for which most students need explicit instruction and guided practice.

Applying Deliberate Practice to Writing

The first step in deliberate practice is for a teacher to divide the skill into manageable chunks and provide students with repeated practice in whatever chunk is appropriate. The teacher also needs to provide prompt, targeted feedback. When students no longer struggle with one chunk, the teacher provides practice in another one, in order to maintain the “desirable difficulties” that lead to learning.

Once students have the basics of a skill stored in long-term memory, their working memory will have more capacity for higher-order tasks. After a violinist has memorized the proper fingering to the point where it’s become automatic, for example, she can focus on other things, such as playing with expression.

Because of their complexity, some writing skills will never become completely automatic. But with deliberate practice, the cognitive load such skills impose can be dramatically lessened. It’s easier to vary your sentence structure, for example, once you have a toolbox of various sentence types stored in long-term memory.

That leads us to the “chunk” we should begin with when applying deliberate practice to writing: sentences. If students haven’t yet learned to construct good sentences, that’s where instruction should start—no matter what age they are or grade level they’re in. That’s true for several reasons. First, if writing is hard, then writing at length only makes it harder. Beginning at the sentence level is a way to modulate cognitive load.

In addition, it makes sense to start with sentences because a student who can’t write a good sentence is unlikely to write a good paragraph or essay. Sentence-level instruction also makes it easier to teach grammar and conventions in the context of students’ own writing; if you’re confronted with pages of error-filled prose, it’s hard to know where to begin.

Sentence-level activities, when well-constructed, can also identify misconceptions or gaps in knowledge before it’s too late. In addition, as I mentioned, they can familiarize students with the complex syntax of written language, boosting their reading comprehension. And when they’re constructed thoughtfully, even sentence-level activities can reinforce knowledge and develop analytical abilities.

Consider the sentence-combining activity involving Rachel Carson. Even though sentence combining can help familiarize students with complex syntax, it isn’t a form of retrieval practice because all the information students need to construct a complex sentence is provided in the simple sentences.

What if, instead, after learning what an appositive is and learning about Rachel Carson, students were given this sentence to complete:

Rachel Carson, ___________________________, grew up in the rural river town of Springdale, Pennsylvania.

Now students are not only constructing an appositive, they’re also retrieving information they’ve learned about Carson and putting it into their own words.

What Makes a Sentence a Sentence?

There are a number of grammatical concepts that can help students both write and understand sentences. In addition to appositives, for example, it’s useful to understand subordinating conjunctions—and we should teach such concepts explicitly. It makes sense to begin instruction with the concept of what makes a sentence a sentence: a basic concept, but one that is not always easy to grasp.

For most students, providing a definition such as “A sentence consists of a subject and a predicate and expresses a complete thought” is unlikely to be enough. Even if they get the idea of a subject and a predicate, determining whether a group of words expresses a complete thought can be tricky. Years ago, when I was trying to tutor some high school students in writing, I showed them this group of words: Although I drank the glass of water. All four of them thought it was a sentence. After all, it had a subject and a predicate, began with a capital letter, and ended with a period.

A company in England called No More Marking, which evaluates student writing across many schools in different countries, has found that students struggle to write sentences, often producing run-ons and fragments. In an attempt to understand the problem, they administered a quiz to about 2,000 students in the equivalent of 4th grade. The students were given a list of phrases and told they needed to choose the one that was a correct sentence. One question gave them the following possibilities:

A) A great film.

B) A great film is.

C) Fascinating films.

D) Enjoyed the film.

E) She watched a great film.

On that question, 91 percent of the students chose the right answer, E. 

On the next question, with the same instructions, students got these choices: 

A) He scowled.

B) The silent crowd.

C) The silent and unhappy crowd.

D) Scowled at the screen.

E) The silent crowd scowled at the camera and.

On that question, only 13 percent identified A as the right answer. Why the difference? Daisy Christodoulou (2023), the director of education at No More Marking, suggested that if students don’t truly understand what makes a sentence a sentence, they focus on surface features—such as length. In the second question, the correct answer consists of only two words, and students apparently felt that was too short to qualify as a complete sentence.

An abstract definition might not work, but teachers can use deliberate practice to help students understand the concept of a sentence. They might provide several groups of words with no punctuation or capitalization and have students distinguish the complete sentences from the sentence fragments. Eventually, through repeated practice and feedback, students will develop a sense of the difference between the two. (This activity and others I’m describing are part of The Writing Revolution method, which is described in a book by that name that I coauthored with Judith C. Hochman.)

Even when working with sentences, it’s important to modulate students’ cognitive load. When first introducing the distinction between fragments and sentences—or any new grammatical concept—it’s best to do so orally and in the context of familiar material. The content could be something already thoroughly covered in the curriculum, or it could draw on the kind of knowledge all students are likely to have. A teacher might say “Ted and Linda” and ask if those words tell us what Ted and Linda did. Then the teacher might say “ate in a restaurant” and ask if those words tell us who ate in a restaurant.

Once students have the basic idea, it’s time to embed the activity in content they’re currently learning. If the class has been learning about maps, for example, one group of words on the list might be “shows the cardinal directions.” After identifying that as a fragment, students need to turn it into a complete sentence by adding the missing information. They might write, “A compass rose shows the cardinal directions.” In retrieving that information from long-term memory and putting it into their own words, students will be consolidating recently acquired knowledge and making it easier to summon up in the future.

Writing instruction has tremendous potential power as a lever for reinforcing knowledge and deepening learning. But because writing imposes such an overwhelming cognitive load, many students never get those potential benefits. If we make writing less difficult for students, we can enable them to become not only better writers but also more effective and engaged learners.

Source: From Beyond the Science of Reading: Connecting Literacy Instruction to the Science of Learning (pp. 130–135), by N. Wexler, 2025, ASCD. Copyright 2025 by Natalie Wexler. Adapted with permission.