Why Your Child Understands Maths in Lessons but Gets It Wrong in Tests

4 minute read

It’s something many parents find both confusing and frustrating: 

“My child understands it when they’re learning it… so why are they getting it wrong in tests?”

You might see them follow along in class, complete homework, and even say they feel confident — only for their test results to tell a different story.

If this sounds familiar, you’re not alone. This is a very common issue in GCSE maths, and there is usually a clear reason behind it.

Having worked with students at GCSE level, this is something I see regularly — and it’s often much easier to fix than it first appears.

Why this happens

One of the main reasons is what we might call the illusion of learning.

In lessons, students often feel like they understand because they can follow along while the teacher is explaining or when they’re copying a method. But this is very different from being able to apply that knowledge independently.

Another key factor is prior knowledge. If a student doesn’t have the necessary foundations in place, new topics become much harder to understand. Learning builds on what has come before — and if something is missing, it can create confusion later on. 

A further important factor is retrieval. For knowledge to stick, students need to actively recall it from memory over time — not just recognise it when they see it. When this doesn’t happen, understanding can feel secure in the moment but quickly fade.

A further issue comes from the difference between familiar and unfamiliar problems. In lessons, students often practise questions that closely follow examples. In tests, questions are slightly different. If a student has understood the concept properly, they will be able to adapt. If not, they can struggle — even if they felt confident beforehand.

What actually works

To move from “I think I understand” to real, secure understanding, lessons need to be carefully structured.

Effective learning often begins with revisiting prior knowledge. This helps strengthen memory and prepares students to connect new ideas to what they already know. 

When new content is introduced, it needs to be explained clearly and broken down into manageable steps. Strong explanations link new ideas to existing knowledge, use clear examples, and make abstract concepts easier to understand. 

After this, students benefit from seeing worked examples and being guided through problems step by step. Over time, this support is gradually reduced so they can begin to apply the method themselves.

Careful questioning is also essential. By asking the right questions and giving students time to think, we can check understanding, deepen thinking, and ensure every student is involved in the learning process. 

Finally, students need opportunities to practise in stages:

• First with guidance 

• Then with support 

• And eventually independently 

This gradual approach helps build both skill and confidence before students are expected to work entirely on their own. 

How I help students move from understanding to results

In my tutoring, I focus on making sure understanding is genuine — not just surface-level.

Each lesson follows a clear structure. We begin by revisiting key ideas to strengthen memory and identify any gaps. We then move on to carefully explained new content, building on what the student already knows.

From there, we work through problems together before gradually moving towards independent practice. This ensures students are fully supported as they develop their understanding.

Throughout the lesson, I use targeted questioning and short activities to check understanding properly — not just by asking “Do you get it?”, but by seeing whether the student can actually apply what they’ve learned.

This allows me to quickly identify misconceptions and address them straight away.

By the end of each session, students have a clear sense of what they can do — and what they need to work on next.

Over time, this structured approach helps students move from simply recognising methods to truly understanding how and when to use them.

This not only improves their results, but also their confidence — which is often the biggest turning point.

If your child is not getting the results they’re capable of

If your child seems to understand maths but isn’t getting the results they’re capable of, there is usually a clear reason — and more importantly, a clear way forward.

If you’d like to understand how I can help, you can book a free consultation where we’ll talk through your child’s current position and create a clear plan to help them move forward with confidence.