Research School Network: Cognitive Load Theory and what it means for classroom teachers What simple steps can you take to avoid overloading your students?

By Andy Tharby

In this post, we shall first consider what research evidence tells us about Cognitive Load Theory, and second some useful principles for classroom practice.

Our working memory, which we use for language comprehension, problem solving and planning, has a very small capacity. We can only hold on to a limited number of items at once – between 3 and 5 for young adults depending on the difficulty of the task – and there are differences in capacity between individual people.

Susan E. Gatherscole and Tracy Packiam Alloway (2007) note the stark differences that can occur in the average class:

“… in a typical class of 30 children aged 7 to 8 years, we would expect at least three of them to have the working memory capacities of the average 4‑year-old child and three others to have the capacities of the average 11-year-old child which is quite close to adult levels.”

Working memory capacity difference, therefore, is one of the main reasons why some students learn less than other students from the same teacher input. However, we should also be aware that the working memory capacity of all humans is very small, even those with a larger than average capacity.

Cognitive Load Theory, developed from the work of John Sweller, is based on the types of information held in working-memory at any one time. These are known as intrinsic load, extraneous load and germane load and, added together, make up the capacity of the working memory. Cognitive overload occurs when the capacity of the working memory is exceeded. Once this happens, we are unlikely to be able to transfer the new information into our long-term memory. In essence, we learn very little.

Intrinsic load is related to the inherent difficulty of the subject matter being learnt. It is influenced by how complex the material is and how much a student already knows about the topic. For example, 2 + 2 + 4 has less intrinsic load than 93 x 543, whereas understanding the workings of the human respiratory system has more intrinsic load than knowing where the lungs are situated in a human body. Intrinsic load is fixed and unchangeable – although there are some nifty ways of helping to reduce its influence.

Extraneous load is bad for learning because it can hinder the construction of long-term memories. It is any extra and unnecessary thinking that students have to do that does not contribute to learning. Unlike intrinsic load, extraneous load is related to how the subject material is presented rather than its inherent difficulty and, as teachers, we can either heighten or reduce its effect. Unfortunately, many teachers remain unaware that their well-meaning efforts actively increase extraneous load.

The third type of cognitive load, germane load, is desirable. It is the load placed on working memory that contributes directly to genuine learning. In other words, the nourishing and productive thinking that causes our students to form and consolidate long-term memories.

Therefore, effective teaching should:

1. Remain mindful of the intrinsic load of the task;
2. Reduce extraneous load;
3. Increase germane load.

Applying Cognitive Load Theory to classroom practice

The advice that follows comes from the extremely useful Cognitive load theory in practice: Examples for the classroom that was recently published by the Department for Education in New South Wales, Australia:

Strategy 1: Tailor lessons according to students’ existing knowledge and skill

Strategy 2: Use lots of worked examples to teach students new content and skills

Strategy 3: Gradually increase independent problem-solving as students become more proficient

Strategy 4: Cut out inessential information

Strategy 5: Present all essential information together

Strategy 6: Simplify complex information by presenting it both orally and visually

Strategy 7: Encourage students to imagine concepts and procedures that they have learnt

What does this mean, therefore, for day-to-day lesson planning? Here are four questions that we believe all teachers and curriculum departments should refer to when reviewing their approach to lesson planning and curriculum planning:

1. Have students studied an example of the new content or skill to be learnt? If not, what should this example look like and where should it be positioned in the lesson and/​or sequence of lessons?

2. At what point should students be working independently without scaffolds? Is this too early, or is this too late?

3. Which resources or content areas do not contribute to the essential concepts that students need to learn in this subject? Where have resources and the curriculum been adapted and/​or slim-lined to allow more room for these?

4. Has the content been presented visually as well as verbally? If not, how could images, diagrams or spatial organisers be incorporated into learning resources and slideshow presentations?