Two Techniques for Lowering the Cognitive Demands of Open-Ended Tasks

How goal-free problems and scaffolding can help students show what they know

Open-ended tasks can be a powerful way to assess deep understanding. When we invite students to write essays, explain a process, or compare historical events, we give them space to synthesise ideas and demonstrate how well they’ve organised knowledge. These tasks can feel authentic, expansive, and aligned with the real work of the discipline.

But they can also be overwhelming.

In a recent post, we explored when and why to use open-ended assessment tasks. We argued that open-endedness is not simply a matter of task format or preference—it arises from the nature of disciplinary knowledge. In subjects where knowledge is cumulative, interpretative, and less tightly sequenced — such as history, literature, geography, or art — open-ended tasks are often necessary to allow students to demonstrate the breadth and depth of their understanding. These tasks mirror the reasoning processes valued in the discipline, such as forming arguments, interpreting evidence, or making evaluative judgements.

Yet the benefits of open-ended assessment must be weighed against their cognitive demands. As we wrote in our piece on the cognitive processes involved in assessment, a student must activate relevant knowledge using cues, select from a pool of partially recalled ideas, and form a coherent response. Each of these stages taxes working memory and demands attention. When a task is too open—or too complex—students may flounder, not because they lack knowledge, but because the cognitive load exceeds their processing capacity.

So how do we manage this?

This post introduces two techniques that teachers can use to lower the cognitive load of open-ended tasks, without making them trivial.

Use goal-free tasks to lower pressure without lowering difficulty

According to cognitive load theory, working memory has a limited capacity for processing new information, especially when tasks involve multiple interacting elements. Open-ended assessment tasks, by their nature, often place a high intrinsic cognitive load on students, because they must simultaneously retrieve knowledge, decide what is relevant, and organise it into a coherent response. If that load exceeds a student’s capacity, even well-learned knowledge can become inaccessible or poorly expressed.

One way to reduce this load is by removing the need to work towards a single, specific goal. A goal-free task is an open prompt that allows students to share what they know without aiming for a narrow end point. For example:

Goal-based task: “Why is the Amazon rainforest under threat?”
Goal-free task: “Tell me as much as you can about the Amazon rainforest.”

The second question is no easier in terms of the knowledge required—both invite students to recall ideas about the Amazon’s location, climate, biodiversity, indigenous communities, economic uses, and environmental threats. But what changes is the cognitive demand of the task. A goal-free prompt like “Tell me as much as you can about the Amazon rainforest” primarily supports activation: it helps students retrieve relevant knowledge from long-term memory without the burden of deciding which information is most pertinent to a particular argument. Because there's no specific outcome to work towards, the student is under less pressure to filter (selection) or structure (response formation) their ideas precisely. As we explained in our earlier post on the cognitive processes involved in assessment, a well-phrased open prompt can act as a strong cue for activation—particularly when we aren't trying to test students’ ability to evaluate or argue, but simply to bring relevant knowledge to mind.

Research has shown that goal-free problems can result in better learning than tightly structured tasks, particularly because they promote broad retrieval and flexible organisation of knowledge. They are especially helpful during the learning process, when we are still building students’ schemas and connections. One practical use might be to begin a lesson with a 10-minute goal-free task, followed by 5 minutes of self-marking or discussion. For example: “Write down everything you can remember about river erosion”. This provides a low-stakes opportunity for students to activate prior knowledge, while also helping teachers gauge what has been retained. Cognitive load theory suggests this works well because it focuses students’ attention on retrieval (activation), without overburdening them with the need to organise or argue. And as we’ve discussed previously, retrieval itself is a powerful learning mechanism—not just a means of assessment.

However, goal-free tasks are not a panacea. They do not provide strong signals to students about what to focus on, how to organise ideas, or how much is enough. Without a clear goal, students may wander into tangents, fail to activate the most relevant knowledge, or interpret the task in unintended ways. We might get a lot of interesting answers, but not necessarily the ones that show what students have learnt from the curriculum.

Used judiciously, goal-free tasks can reduce pressure and improve fluency. But they should be clearly framed, and we must be mindful of what knowledge they are likely to activate.

Use scaffolding to support response formation

The second strategy for reducing the cognitive load of open-ended tasks is more familiar: break the task down.

Scaffolding involves structuring the response process so that students can focus on one part of the task at a time. In doing so, we reduce the load on working memory and support the final stage of the cognitive process - response formation. Students are no longer juggling all the ideas in their head while trying to form a fluent paragraph. Instead, they can build their answer step by step.

Consider a task that asks students to compare two poems. An open-ended version might say: “Compare how the poets present the theme of power in these two texts.”

A scaffolded version might offer: “Start by explaining how the theme of power is presented in Poem A. Then describe how it is presented in Poem B. Finally, write a paragraph comparing the two approaches.”

Scaffolding makes a cognitively demanding task more manageable by breaking it into smaller, sequenced steps. But this support comes at a cost. It doesn’t just lighten the load—it fundamentally alters the nature of the assessment and the type of cognition it demands. Instead of asking students to independently decide what knowledge to use, how to structure it, and how to express it fluently, we are guiding them through a series of smaller, more specific tasks. In doing so, we reduce the demands on selection and response formation, and the inferences we can draw are correspondingly narrower. What we learn is whether students can complete the steps, not whether they can plan and execute the overall task.

As with goal-free tasks, the challenge is one of balance. Scaffolding is invaluable when students are novices, when we want to teach response strategies explicitly, or when we want to reduce anxiety. But if we want to assess whether students can handle the full cognitive complexity of a domain, we will eventually need to remove the supports and let them work more autonomously.

That’s why scaffolding must always be provisional. Ultimately, students must learn how to manage their own cognitive load—not just by mastering the content, but by learning how to structure their thinking, manage working memory, and pace their response. A student who sits down to write an extended essay with no scaffolding needs to build it for themselves: identifying the question’s cues (activation), selecting what matters, and forming a coherent structure. Good assessment practice supports this transition—not by permanently reducing complexity, but by gradually handing over the cognitive work to the student.

Bringing it together

Both techniques—goal-free design and scaffolding—are tools for managing the cognitive demands of open-ended assessment. Used well, they allow students to demonstrate what they know without being overwhelmed by the mental effort required to navigate task structure. But these are not neutral supports. Each reshapes the nature of the task, alters the type of thinking involved, and changes what we can infer about student understanding.

• Use goal-free tasks to encourage wide-ranging retrieval, particularly during the learning process when we want to activate knowledge without requiring precise structure or judgement.

• Use scaffolding when the barrier is not content knowledge but the ability to organise, express, or manage the response—especially when teaching new formats or building student confidence.

But we must also be clear-eyed about the trade-offs. Goal-free tasks reduce precision. Scaffolds reduce independence. If we rely on them too heavily, we risk obscuring the very thinking we are trying to assess.

That’s why managing cognitive load is not just a matter of designing better tasks—it is part of a broader educational aim: to equip students to manage complexity themselves. Our end goal is not to remove difficulty but to build the cognitive strength, strategies, and resilience that allow students to face difficult tasks unaided.

If we want assessment to serve learning, we cannot treat open-ended tasks as a neutral mirror of what students know. We must recognise how task design shapes thinking, how thinking is constrained by cognitive architecture, and how our teaching—and our assessments—can prepare students to think well under pressure.