Designing Resources That Do Not Overload

I’ve sat through enough CPD sessions to know the drill: a consultant in a crisp shirt stands at the front of a room, presenting slick slides about how cognitive load theory applies to “idealised learners.” They make it sound like a simple matter of swapping a font or colour-coding a worksheet, as if you aren’t currently staring down a Year 10 class that is actively trying to dismantle your lesson plan. It’s easy to talk about working memory when you aren’t dealing with thirty kids, three of whom are currently having a disagreement over a stolen glue stick.

I’m not here to give you more theory to add to the pile of things you don’t have time to implement. Instead, I want to talk about what actually happens when you try to manage that mental load in a room that is loud, messy, and unpredictable. We’re going to look at the practical, gritty reality of simplifying your instructions and structuring your slides without turning your teaching into a lifeless script. This is about making the science work for you, not the other way around, so you can actually get through the lesson without everyone—including yourself—feeling completely burnt out.

Decoding Cognitive Architecture and Learning Without the Academic Fluff

Look, we can spend all day debating the finer points of cognitive architecture and learning, but let’s be honest: most of the academic papers on this subject feel like they were written by people who haven’t stepped foot in a classroom since the nineties. When you strip away the jargon, the theory is actually quite simple. It’s about the fact that our brains have a finite amount of “working memory” space. Think of it like a small desk in a crowded classroom; if you pile too many textbooks, loose papers, and half-eaten snacks on it at once, there’s nowhere left to actually do the work.

In practice, this means we have to get smart about intrinsic vs extraneous cognitive load. The “intrinsic” part is the actual difficulty of the topic—you can’t make the French Revolution any simpler, but you can control the noise. The “extraneous” part is the rubbish that gets in the way: a cluttered PowerPoint, a confusing worksheet, or a teacher who talks too fast while writing on the board. Our job isn’t to make the content easy, but to stop the clutter from stealing the mental energy students need to actually learn.

Managing Intrinsic vs Extraneous Cognitive Load in a Chaotic Room

Now, let’s get practical. In the theory books, distinguishing between intrinsic vs extraneous cognitive load is a clean, mathematical exercise. In a classroom where a radiator is clanking and a Year 10 is currently trying to balance a ruler on their nose, it’s much messier. Intrinsic load is simply the inherent difficulty of the task—you can’t make the French Revolution “easy,” but you can control how you introduce it. The real battle, however, is the extraneous load: all that unnecessary mental noise that eats up a student’s limited processing power before they’ve even grasped the concept.

If your PowerPoint is a graveyard of clip art, neon colours, and walls of text, you aren’t helping them learn; you’re just making them work harder to filter out your bad instructional design principles. When we talk about minimizing mental effort in learning, we aren’t talking about making things “easy” or “dumbing it down.” We are talking about clearing the debris off the road so they can actually see the destination. If they are spending all their energy trying to decipher your handwriting or find the relevant bit of a cluttered worksheet, they have nothing left for the actual thinking.

Five ways to stop overloading your students (without losing your mind)

• Stop the slide-deck deluge. We’ve all seen that teacher who treats a PowerPoint like a digital novel, cramming every single word onto the screen. If they’re busy reading your slide, they aren’t listening to you, and their working memory is already red-lining. Give them the key terms, keep the rest verbal, or better yet, give them a printed handout so they aren’t playing a frantic game of ‘copy from the board’ while trying to actually process the concept.
• The ‘one thing at a time’ rule for instructions. When I’m standing in front of a restless Year 10 class, I’ve learned that giving three instructions at once is just noise. “Get your books out, turn to page forty, and start the retrieval task” sounds simple, but by the time they’ve found the book, half the class has forgotten the task and is staring at the ceiling. Give one instruction, wait for the silence, then give the next. It feels slow, but it’s actually faster.
• Use worked examples, but don’t let them become a crutch. Showing a fully worked mathematical problem or a model essay paragraph is brilliant for reducing that initial cognitive heavy lifting. But if you just show them the finished product and say “now you do it,” you’ve failed them. They need to see the process—the ‘why’ behind each step—otherwise, they’re just mimicking a pattern without any actual understanding.
• Scaffolding isn’t just a buzzword; it’s your safety net. If you’re introducing a complex new topic, don’t throw them into the deep end of a blank page. Provide sentence starters, writing frames, or even just a list of key vocabulary on the desk. It’s not “dumbing it down”; it’s clearing the mental clutter so they can focus on the actual thinking, rather than struggling to remember how to structure a sentence.
• Beware the ‘split-attention’ trap in your resources. If you have a diagram on one page and the explanation of that diagram on another, you are actively sabotaging their learning. Their brains are working overtime just trying to shuttle their eyes back and forth. Keep the labels on the diagram, keep the text right next to the image, and let them focus on the content, not the logistics of reading your worksheet.

The Reality Check: Three ways to actually use this

Stop over-complicating your slides; if your PowerPoint looks like a digital textbook, you’re just adding noise that their brains can’t process while they’re also trying to listen to you.

Prioritise the ‘must-knows’ over the ‘nice-to-knows’—trying to cram a massive curriculum into one lesson is a recipe for cognitive overload, and it’s your students who pay the price.

Use worked examples as a safety net, not a crutch; showing them the step-by-step process isn’t ‘spoon-feeding’, it’s providing the scaffolding they need so they don’t freeze up when the pressure is on.

## The Reality Check

“We can spend all day debating the nuances of working memory capacity in a seminar room, but the real test of cognitive load theory isn’t found in a textbook; it’s found in whether your Year 10s can actually process a single instruction while the radiator is clanking, the person behind them is whispering, and you’re trying to explain a concept that’s already three steps ahead of their ability to hold it.”

Ellery Mwangi-Selkirk

The Reality Check

Look, we can debate the nuances of working memory capacity until the bell rings for lunch, but at the end of the day, it comes down to one thing: don’t overwhelm them. We’ve talked about stripping away the decorative nonsense that clutters a slide and why managing that intrinsic load is the difference between a student grasping a concept and a student simply staring blankly at the whiteboard. It isn’t about being a perfect practitioner or implementing some high-concept pedagogical framework; it’s about being ruthlessly efficient with the limited mental bandwidth your pupils have available to them. If you can reduce the friction of how they access information, you’ve already won half the battle.

I know it feels like there is always one more initiative to master or one more theory to squeeze into a lesson plan, but please, give yourself some grace. You aren’t a cognitive scientist; you’re a teacher trying to make sense of a room full of living, breathing, often distracted human beings. Focus on the small, practical shifts—the clearer instructions, the simplified diagrams, the pauses that actually allow for processing. Those are the things that survive the chaos of a Tuesday afternoon. You don’t need to reinvent the wheel; you just need to make sure the wheel actually turns when the pressure is on.

About Ellery Mwangi-Selkirk

Most educational advice is written for a classroom that does not exist — twenty motivated pupils, unlimited preparation time, no behaviour to manage. I write for the room you are actually in. What retrieval practice looks like when marking is already three weeks behind, why the seating plan matters more than the starter activity, and which of the last decade's initiatives left anything behind. Nineteen years taught me that the good ideas survive contact with a wet Wednesday and the rest do not.