Year 8 Science · Unit 4 · Lesson 11
Apply Worksheet
Learning Goals
Find the flaw
A student's CER response about a plant growth investigation contains three errors, one in each part. For each row: (1) explain what is wrong, and (2) write an improved version. The investigation question was: "Does the amount of light a plant receives affect its height after two weeks?"
| CER part | Student's original (flawed) | What is wrong with it? | Your improved version |
|---|---|---|---|
| Claim | "The experiment worked well." | ||
| Evidence | "The results showed a trend." | ||
| Reasoning | "Because science." |
Hint for improved claim: plants in 8 hours light grew to 22 cm; plants in 2 hours light grew to 9 cm.
Plant growth data
Four fertilisers were tested on identical pea seedlings grown under the same conditions over 3 weeks. Average final heights: Fertiliser A = 24 cm, Fertiliser B = 18 cm, Fertiliser C = 31 cm, Fertiliser D = 12 cm. A control group (no fertiliser) reached an average height of 10 cm. All other conditions, light, water, soil type, temperature, were kept the same.
Write a full CER response to the question: "Which fertiliser produced the best plant growth?" Use the scaffolded boxes below.
Claim Write one clear sentence that answers the investigation question.
Evidence Quote at least two specific data values from the investigation to support your claim.
Reasoning Explain in 1–2 sentences why your chosen fertiliser produced better growth. Use ideas about nutrients, photosynthesis, or plant biology.
1. A student writes: "The dissolving time decreased as temperature increased." Is this a claim, evidence, or reasoning? Explain your answer and improve it to make it a complete CER element of that type.
2. Why is reasoning the most challenging part of the CER framework? What happens to a scientific argument when reasoning is missing?
Wrap Up
In one sentence, what was the main idea of this lesson?