The CER method: connect a claim to evidence with reasoning
CER stands for Claim, Evidence and Reasoning. A claim states your answer, evidence supplies support and reasoning explains why that support makes the claim convincing. It is commonly used in science explanations.
Before you start
'Here is my opinion, and here is a fact' is only the start of an argument. The reader still needs to understand the connection. CER makes you write that connection rather than hoping it is obvious.
The guide below adapts the reasoning check for persuasive writing practice. In a science task, evidence should come from observations or data. A possible example in an opinion piece can illustrate a reason, but it cannot establish a measured result.
Step by step
Claim: answer the question
State what you want the reader to accept. Keep it narrow enough to support. 'The school should label its recycling bins clearly' can be developed in a paragraph; 'Everyone should save the planet' needs much more explanation.
Evidence: identify the support
Use relevant information. When practising with a made-up scenario, label its details as practice data. When writing about a real event, check that you can honestly describe what happened. Do not invent an experiment or a source.
Reasoning: explain the connection
Show why the evidence supports the claim. Identify the useful principle, cause or consequence. If a sign helps someone choose the correct bin, explain how that reduces confusion. Repeating the data is not reasoning.
Worked CER example: clearer bin labels
Invented practice data: In a classroom sorting activity, four groups place the same yoghurt container in different bins. After reading labels that list accepted items, all four choose the container bin. These results are fictional and must not be presented as real research.
Claim
Our school should label its sorting bins with examples of the items each bin accepts.
Evidence
In this practice scenario, groups made different choices before seeing the labels and the same choice after reading them.
Reasoning
Examples on a label help students match the object in their hand to the correct destination. Clearer instructions could therefore reduce sorting mistakes caused by uncertainty.
Check how far the evidence reaches
One example does not establish what every student will do. Match the strength of your claim to the support you have. 'Could reduce confusion' is more defensible here than 'Will eliminate every mistake'.
Begin with a because sentence that connects the example to the claim. Then name one question the example leaves unanswered.
Spot the reasoning gap
A weak paragraph says labels help because labels are helpful. That restates the claim. A stronger paragraph explains how naming accepted items helps a student make a choice.
CER can help you revise a TEEL or PEEL paragraph. Find the point, the support and the explanation. If the explanation is missing, add it. CER alone does not plan the introduction and conclusion of a complete persuasive response.
Try it yourself
Should a school put a picture of the expected lunchbox contents beside its food-waste bin?
- State a specific recommendation.
- Describe a possible confusion the picture could address, marking it as a hypothetical example.
- Explain how the picture would help someone choose.
- Check whether your conclusion claims more than the example supports.
Check your draft
Read your reasoning without the evidence. Does it explain a connection, or merely repeat that your proposal is good?
Common questions
What is the difference between evidence and reasoning?
Evidence is the information supporting a claim. Reasoning is the explanation of why that information supports it. A list of facts still needs a connection to the point.
Is CER an official NAPLAN paragraph requirement?
No. It is a teaching framework you can use to check an argument. Follow the task's text type and develop a connected response rather than treating the letters as a compulsory format.
Can I make up data for CER?
Only in an explicitly fictional practice scenario such as the example here. In a real science or research task, report the data you actually have. In persuasive practice, label imagined situations as examples rather than studies.
Curriculum connection
These exercises practise planning, organising and revising written ideas. Australian Curriculum English includes creating texts for an audience and grouping related information into paragraphs. TEEL, PEEL and the other planning methods are teaching aids, not compulsory curriculum formats.
QCAA: Australian Curriculum v9.0 English, Year 3Sources and further reading
These resources provide background on the skill. The examples and practice tasks above are original.
Check the reasoning in a full response
Open writing practice and check one argument for a claim, relevant support and an explanation. Use CER to find any missing connection.
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Examples and activities are NAPLAN Expert teaching material. Sources checked in October 2026.