True, and still misleading: reading a graph critically
The Short Answer
A misleading graph is almost never one with wrong numbers on it. Every value is usually correct and what is wrong is the impression a reader takes away. So the question is never whether the numbers are right — it is whether the picture agrees with them. Say the claim first, then check the scale, the pictures and what is missing.
What is a misleading data question?
Your child is shown a chart and asked what is wrong with it, or whether a claim made about it is fair.
Here is the thing to understand first, because everything else follows from it:
A misleading graph is almost never a graph with wrong numbers on it. Every value is usually correct. What is wrong is the impression — and the impression is what a reader takes away.
So your child is never asking are these numbers right? They are asking does the picture agree with them?
The Second Look
Four checks, always in this order.
Say the claim. Out loud, or under your breath. This chart says sales have tripled.
Check the scale. Where does the axis start? Are the steps equal?
Check the pictures and the shapes. A pictogram scaled in two directions exaggerates.
Ask what is missing, and answer the question that was asked.
The order is not decoration. Saying the claim first gives you something to test the figures against. Skip it and you are staring at a graph hoping to notice something, which works about half the time — and half is not good enough.
The truncated axis
The other three
Unequal steps. A time axis running 2019, 2020, 2022, 2025 at equal spacing draws a three-year gap the same width as a one-year gap. Any trend read off that shape is distorted.
Pictures scaled two ways. A pictogram where a bigger group gets a bigger figure — taller and wider — exaggerates, because the eye compares areas, not heights. Double both dimensions and it looks four times as big.
What is missing. No total. No labels. A percentage with no statement of what it is a percentage of. A chart that leaves out the one number needed to judge the claim is misleading by omission.
Where do pupils lose marks?
Stopping at the first problem they find.
Saying the numbers are wrong, when they are right and the picture is not.
Skipping the claim, and having nothing to test against.
Answering a different problem from the one the question asked about.
Try it yourself
Say the claim out loud first. Then run all four checks, even after you have found something.
- A bar chart's vertical axis starts at 90 rather than 0. What effect does that have?
- A chart shows sales of 102, 104 and 106 with the axis starting at 100. The bars look three times different. Are the numbers wrong?
- A time axis runs 2019, 2020, 2022, 2025 at equal spacing. What is the problem?
- A pictogram uses a picture of a person for 10 people, but draws a bigger person for a bigger group. Why is that misleading?
- Why is finding one problem and stopping the most expensive habit on this topic?
- It exaggerates the differences. Bars that are close in value look dramatically different, because the shared portion below 90 has been cut away.
- No — every value is correct. The chart is misleading rather than wrong, which is the whole idea. The heights differ by a factor of three because only the top six units are shown.
- The steps are unequal but drawn as though equal, so a three-year gap occupies the same width as a one-year gap. Any trend read off that shape is distorted.
- Because the eye compares areas, not heights. Doubling both the height and the width of a figure makes it look four times as big, when it should represent twice as many.
- Because a transfer-test chart often carries two problems at once and the question is only about one of them. A child who finds the truncated axis and stops may never notice the missing total that the question was actually about.
How much practice does this type need at home?
This is the one topic where the practice material arrives free, daily, and unprompted.
Charts built to create an impression are in newspapers, adverts and social media constantly. Point at one and ask two questions: what is this trying to make me think, and where does the axis start?
A child who asks those two things automatically has been given something considerably more valuable than a mark on a paper — and unlike most of what is on the paper, they will still be using it at thirty.
Free: a Maths workbook
Questions across the Maths question types, with the method printed at the top and full answers at the back. One workbook for the whole strand, not a sheet per question type.
Frequently Asked Questions
What does 'true and still misleading' mean?
That the numbers printed on the chart are correct and the picture still tells a lie. If sales of 102, 104 and 106 are drawn on an axis starting at 100, the bars are in the ratio 2 : 4 : 6 and look wildly different — while the actual sales barely moved. Nothing is inaccurate. The impression is false, and the impression is what a reader takes away.
What are the four checks?
Say the claim. Check the scale — where the axis starts and whether the steps are equal. Check the pictures and the shapes, since a pictogram scaled in two directions exaggerates. Then ask what is missing, and answer the question that was asked. The order matters: saying the claim first gives you something to test the figures against, and without it you are staring at a graph hoping to notice something.
Why check all four when I have found the problem?
Because a real transfer-test chart will often carry two problems at once — a truncated axis and a missing total, say — and the question will only be about one of them. Finding one thing wrong and stopping is the single most expensive habit on this topic, because it feels like success.
Is this worth teaching beyond the exam?
More than almost anything else on the paper. Charts designed to create a false impression are in newspapers, advertising and social media every day, and a child who instinctively looks at where the axis starts has been given something that will outlast the 11+ by a long way. It is one of the few topics where the exam skill and the life skill are identical.
Sources
- GL Assessment — 11+ familiarisation materials and question type descriptions Published 2025.
- Clever Clogs Academy — our own Year 4 and Year 5 lesson records, Winslow Published September 2025 to July 2026.
We are not affiliated with, endorsed by or connected to GL Assessment or Buckinghamshire Council. Test arrangements change; always check the council's own pages for the current year's dates.
We Teach This Method Every Week in Winslow
Groups of no more than six pupils with two qualified teachers, in person or online. Come and see a session before you decide.