Science Year 8 - Unit 2 - Lesson 9

How Atomic Models Changed Over Time

Use this worksheet after reading the lesson to practise the key ideas and prove you can meet the success criteria.

Name

Date

Class

1. Key Ideas

This lesson shifts from atom facts to scientific history, showing how evidence caused atomic models to change over time.

atomic models changed over time
science changes when stronger evidence appears

2. Success Criteria

By the end, you should be able to:

atomic models changed over time
different scientists proposed different models
evidence is the reason models changed

3. Key Terms

Key ideaThe central concept from How Atomic Models Changed Over Time.

EvidenceInformation, observations or calculations used to support an answer.

ExplainGive a reasoned answer that links cause and effect.

ApplyUse a learned idea in a new example, problem or scenario.

4. Activity: Build the Lesson Map

Use the lesson to complete the table. Keep answers brief but specific.

Prompt	Your answer
Main concept
Important example
Common mistake to avoid
How this links to the next lesson

5. Short Answer Questions

1. Explain this lesson goal in your own words: "atomic models changed over time". Use one specific example from the lesson.

Core

2. Apply this idea to a new example: "different scientists proposed different models". Show your reasoning clearly.

Core

3. Analyse why this idea matters for understanding How Atomic Models Changed Over Time: "evidence is the reason models changed".

Reasoning

6. Extend: Apply the Idea

A student says, "I understand How Atomic Models Changed Over Time because I memorised the definition."

Explain why memorising a definition is not enough. Use an example from the lesson to show deeper understanding.

7. Multiple Choice

1. What is the best first step when answering a question about How Atomic Models Changed Over Time?

A. Identify the key concept being tested

B. Write every fact from memory

C. Ignore the command word

D. Skip examples and evidence

2. Which answer would show stronger understanding of How Atomic Models Changed Over Time?

A. An answer with accurate terms and reasoning

B. A copied definition only

C. A single-word response

D. An answer with no example

3. What should you do if a question asks you to explain?

A. Link the idea to a reason or cause

B. List unrelated facts

C. Only draw a diagram

D. Write the shortest possible answer

8. Success Criteria Proof

Finish with evidence that you can do each success criterion.

Success criterion 1

Prove that you can: atomic models changed over time

Success criterion 2

Prove that you can: different scientists proposed different models

Success criterion 3