Grade: 3 Subject: Science Unit: Data Collection Lesson: 5 of 7 SAT: ProblemSolving+DataAnalysis ACT: Science

CER Writing: Data Collection

Example CER

Question: Based on your paper airplane data, which design flew the farthest?

Claim: The basic dart design flew the farthest of all three airplane designs tested.

Evidence: According to my data, the basic dart flew an average of 4.2 meters. The wide wing design averaged 2.8 meters, and my custom design averaged 3.5 meters. The dart's individual trials were 4.0m, 4.5m, and 4.1m, showing consistent results.

Reasoning: This shows that the dart shape is more effective for distance because it is streamlined and cuts through the air with less resistance. The narrow shape creates less drag than the wide wing design. The consistent results across trials also show that the dart design flies reliably, not just by luck.

Practice Questions

1. What makes evidence strong in a data-based CER?

A) Using your opinion
B) Including specific numbers from your data
C) Making up results
D) Using vague descriptions

Answer

B) - Specific numbers and measurements make evidence stronger and more convincing.

2. "My data table shows..." is a good way to introduce:

A) A claim
B) Evidence
C) Reasoning
D) A question

Answer

B) Evidence - This phrase introduces specific data from your experiment.

3. Which is the best CLAIM for an experiment about plant growth?

A) Plants are cool
B) I grew plants
C) Plants grew taller with more sunlight
D) Sunlight exists

Answer

C) - This directly answers a question with a testable scientific statement.

4. A student writes: "Plant A grew 12 cm. Plant B grew 5 cm." What is this?

A) Claim
B) Evidence
C) Reasoning
D) Hypothesis

Answer

B) Evidence - These are specific measurements from an experiment.

5. What should reasoning explain?

A) What you did
B) What materials you used
C) Why the evidence supports your claim
D) What you will do next

Answer

C) - Reasoning connects your data to your claim and explains WHY.

6. "The average was 15 cm" is:

A) Qualitative data
B) Quantitative data
C) An opinion
D) A hypothesis

Answer

B) Quantitative data - Numbers and measurements are quantitative.

7. How can a graph help your CER?

A) It makes the paper longer
B) It provides visual evidence that supports your claim
C) It replaces writing
D) It doesn't help

Answer

B) - Graphs show patterns in data visually, strengthening your evidence.

8. "This proves that..." is a good way to start:

A) A claim
B) Evidence
C) Reasoning
D) A title

Answer

C) Reasoning - This phrase explains how evidence supports the claim.

9. If your data shows unexpected results, your CER should:

A) Hide the results
B) Report the actual data and try to explain it
C) Make up better data
D) Skip the evidence section

Answer

B) - Good scientists report real results and try to understand them.

10. How many pieces of evidence should a strong CER include?

A) 0
B) 1
C) 2-3
D) 50

Answer

C) 2-3 - Multiple pieces of evidence make your argument stronger.

Your Turn!

Write a CER using data from YOUR paper airplane experiment:

  • Claim: The [design name] flew the farthest because...
  • Evidence: Use your specific measurements and averages
  • Reasoning: Explain WHY that design worked better

Next Steps

  • Include a graph with your CER
  • Have a partner check your CER for all three parts
  • Continue to the Unit Checkpoint