Cognitive Load, Considered

It’s a few days after your students took a test on clauses and now you’re beginning a lesson on sentence types. You begin explaining that a simple sentence contains a single clause, but even the students who did well on the test are having trouble remembering what exactly constitutes a clause. Your soul groans with despair.

As educators, we want students to retain information — not just long enough to make it through the end of a unit or assessment but for the long haul. And while it’s unlikely they’ll remember 100% of the material you teach, the more they can store in their long-term memory, the easier it will be for them to build on concepts and ideas in the future.

We often overload students’ working memories with too much information at once, making it difficult for them to recall the really important material between lessons, let alone remember something several weeks into the future. And if the assessment isn’t well-designed, it may not show whether that information is really stored in their long-term memory.

So, what can we do? How can we better support students in remembering material long-term so they can build on those learnings throughout their time with us and into their next grade level?

We must understand and apply the implications of cognitive load theory. 

Short Term Memory and Sea Glass

Imagine you’re walking along a beach, collecting sea glass in a small jar that can contain only about four pieces of glass. You try to put a handful into the jar, but most of the pieces fall out. The jar quickly fills, and you must make a choice: you can part with some of the pieces you’ve collected to make space for new finds or continue on your journey without adding to your collection.

Or, as a third option, you could transfer the sea glass to a magic backpack with unlimited space, freeing up the jar for new treasures.

In this metaphor for cognitive load, the jar serves as a student’s working memory, the backpack is their long-term memory, and the sea glass represents the material you’re teaching. The sea glass that makes its way into the backpack is the information that’s been learned, the acquired knowledge. In cases where learning is lost, the sea glass never makes its way into the backpack. 

According to Cognitive Load Theory (CLT), coined by psychologist John Sweller, students’ working memory can only hold a small amount of information at once (about four new items at a time, according to a study published by Cambridge). We must design learning experiences with this in mind. The implications for this go well beyond avoiding overloading students with extraneous information. 

Schema and Compound Interest

How can we use cognitive load theory to maximize learning? How can we get the most sea glass into the backpack?

Recently, education journalist and author Natalie Wexler guested on the Propello podcast Education Uncharted to discuss the role of long-term memory. Natalie, who wrote The Knowledge Gap and co-authored The Writing Revolution, says tapping into long-term memory is the key to success in reading and writing. 

“The best way around the limits on working memory is to have a lot of stuff stored in long-term memory, which is potentially infinite. And if you can just withdraw relevant information from long-term memory, you don't have to juggle it in working memory along with the new information you're trying to take in,” Natalie says. “You have more capacity to just take stuff in and attend to the meaning and absorb it and retain it.”

The reason for this is that we use the knowledge we already have to gain new knowledge. If we are learning the sounds of the different letters in the word “ocean,” sounding out the word may use all of our short term memory. If we already recognize the combinations of letters as the word “beach,” it takes up very little cognitive load, and we can read a sentence about the various sea life in the Indian Ocean. We are using the knowledge we already have to gain new knowledge. In other words, the jar we use to collect new sea glass is actually made of sea glass from our backpack! 

Our acquired knowledge isn’t just a long list of facts. Knowledge is organized in networks. That means that pieces of knowledge are connected to other pieces of related knowledge. New information needs to attach to existing sets of knowledge called schema. The more schema we have, the more knowledge we can gain. As Warren Buffet has said, knowledge “builds up like compound interest.” 

Natalie points out that a good curriculum builds knowledge by leveraging tactics like discussions and reading aloud — especially for students who are not yet fluent readers. If teachers read a complex text aloud, they are taking on the cognitive load of decoding the words that may be unfamiliar to students, and freeing up space for students to learn the concepts and build knowledge. 

How to Ease Cognitive Load and Leverage Long-Term Memory

As we’ve established, reading aloud to students and promoting discussion follow the tenets of cognitive load theory. Here are a few more strategies educators can do to help ease the burdens on student cognitive load and help them transfer key knowledge to long-term memory: 

• Scaffolding
  We may not think of it that way, but reading aloud to students is a form of scaffolding. As Scarborough’s Rope depicts, reading is composed of two strands: phonetic decoding and comprehension. Reading aloud creates a scaffold of the phonetic decoding to make the task less complex. This allows students to focus on comprehension, storing away more vocabulary and background knowledge, schema that can be used to capture even more knowledge. Other forms of scaffolding are sentence starters, cloze items, and partially complete exercises. 
  
  
• Mnemonic devices
  Mnemonic devices are an excellent way to help introduce new concepts and information to students without overwhelming their working memory. Things like chunking, acronyms, acrostics, rhyming, and association are all proven to help with memory and recall by helping to hold information in the working memory more efficiently.
  
  
• Infographics and Graphic Organizers
  When students perceive an infographic that shows an independent clause as a bike with a subject wheel and a verb wheel, they can later pull that schema out of their long term memory to more easily understand that a compound sentence contains two independent clauses, two bikes. When they pull that visual idea out of their long term memory, they use less short term memory to understand the new concept. We are allowing students to hold more important information at once in their short term memories. 
  
  
• Gradual Release of Responsibility 
  In many cases, we want students to drive their own learning. There is so much knowledge that students can acquire when their curiosity and personal interests are sparked. However, certain skills may be best transferred through a gradual release of responsibility. This is the “I do, we do, you do” lesson structure. Teachers model a new skill; the class completes an example together; then students practice the skill on their own. This allows students to take on pieces of the cognitive load of a task as they are ready for it.  
  
  
• Formative Assessment 
  If the goal is to build upon existing schema in students’ minds, we must use formative assessment to learn what schema they are working with. This includes informal assessment, like beginning a lesson with a discussion or a KWL Chart. Ideally, we want to tap into prior knowledge so we can introduce the right information at the right time. 
   
• Logical Scope and Sequence
  As Natalie pointed out in our podcast, it’s crucial that curriculum is designed to build knowledge. And because knowledge is built and stored in networks of connections, it is essential to introduce related concepts together. In addition, simpler components of skills should appear before those that require more cognitive load. 

Want your students’ magic backpack of long term memory to be chock full of sparkling cities of sea glass? Propello’s grade 6-8 ELA curriculum uses all these strategies and much more. Join the waitlist to take Propello ELA 6-8 for a test flight.

Curriculum that Considers Cognitive Load   

Propello's units are built around Essential Questions so that inquiry drives knowledge-building. Mini-lessons use gradual release of responsibility, infographics, and interactive graphic organizers to teach key reading and language Focus Skills. Texts include scaffolding and embedded Focus Skill practice. Project-based assessments and writing extensions bring each unit’s Essential Questions and Focus Skills together. Formative assessment is everywhere. 

Our customizable learning paths allow you to modify content arrangement. This way, you can return to a skill that hasn’t made its way fully into students’ long term memories, extend a skill for students that are ready for more complexity, and build on knowledge that has especially sparked student interest. 

As a teacher, it can be frustrating when you feel like the material you’re teaching isn’t sinking in. And, often, it’s just as frustrating for students when they’re struggling to grasp a concept. By taking time to better understand the limits of short term memory and how to leverage cognitive load, you can make sure students are carrying knowledge from one unit to the next, compounding their schema and comprehending increasing complexity.