You will learn
- Ask a testable question.
- Plan a fair test.
- Collect and graph data.
- Draw a conclusion about forces.
Version 0.2 · expanded edition · built from cited public sources Content is based on the official frameworks and sources listed under Sources and standards. No official endorsement is claimed. Written in the style of common primary school assessments. No exam result is promised.
Student lesson
- An investigation answers a question.
- We change one variable and measure another.
- We repeat and record.
- We conclude from evidence.
Words to know
a planned test to find an answer
something that can change
the thing we change
the thing we measure
1. Discover: The car race question
Group B asks, “Does the surface change how far a toy car rolls?” They plan to change only the surface and measure the distance. “We will use the same ramp and the same car,” they decide.
Think: Which variable do they change and which do they measure?
2. Understand: Investigations
Idea 1: The question
A good question can be tested: “Does the surface change how far a car rolls?” The independent variable is what we change (the surface). The dependent variable is what we measure (distance).
Idea 2: Fair plan
Keep other variables the same: same ramp, same car, same release point. Repeat three times and record.
Idea 3: Conclusion
Use your table and graph to answer the question, link it to friction and suggest improvements.
3. Worked examples
Example 1 (I show you): Change
Surface.
- Independent.
- We change it.
- Surface.
Answer: The surface is the independent variable.
Example 2 (We do it together): Measure
Distance.
- Dependent.
- We measure it.
- Distance.
Answer: Distance is the dependent variable.
Example 3 (You try): Fair
Same ramp.
Show the steps and answer
- Control.
- Same car.
- Fair.
Answer: Keep other variables the same.
Did you know?
Engineers test new car tyres on many different surfaces before they are sold.
Why this matters
Investigations show how to find reliable answers.
4. Explore: Surface and distance
Complete a full investigation.
- Write the question and prediction.
- Set up a ramp and car.
- Test three surfaces three times each.
- Record, graph and conclude.
Think about it: what did you notice?
What did you notice? Rough surfaces stopped the car sooner, as friction predicts.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- An ___ answers a question.
- We change the ___ variable.
- We measure the ___ variable.
- We ___ the test.
Guided practice
Question 1. What is an investigation?
Planned test.
Question 2. What do we change?
Independent variable.
Question 3. What do we measure?
Dependent variable.
Independent practice
Level 1: Start
- What is an investigation?
- What do we change?
- What do we measure?
- Why repeat?
- What do we conclude from?
Level 2: Grow
- Why keep the ramp the same?
- Why graph results?
- Why link to friction?
Level 3: Stretch
- Plan an investigation.
- Run it.
- Report it.
Answers are in the answer key below. Try first, then check.
6. Apply: Science in everyday life
What force question could you test?
Show a sample answer
Surface and distance.
Another one. Tell a family member one thing from this lesson. Use the words you learned.
Show a sample answer
A clear sentence that uses at least one word from Words to know.
7. Common mistakes
Fix: Change one.
Fix: Repeat.
8. Lesson summary and revision card
- I can ask a testable question.
- I can plan a fair test.
- I can collect and graph data.
- I can draw a conclusion about forces.
9. Check and master
Answer all 14 questions. You will see feedback after each one.
Your result appears here after you answer every question.
10. Key takeaways
- An investigation answers a question.
- We change one variable and measure another.
- We repeat and record.
- We conclude from evidence.
11. Next lesson
Next lesson: Rocks. Keep going with the next idea in this course.
Exam practice
These questions are written in the style of common school and international primary assessments. Try them on your own, without looking back. Then check your answers in the marking guide. The marks are shown in brackets.
- Write a testable question. [2 marks]
- Name the variables. [3 marks]
- Describe a fair plan. [3 marks]
- Write a conclusion. [1 mark]
- Safety rule? [1 mark]
Total: 10 marks.
Marking guide and model answers
- Question [1]; testable [1]
- Independent [1]; dependent [1]; controlled [1]
- Same ramp [1]; repeat [1]; record [1]
- Evidence-based [1]
- Any [1]
Score guide: 9 to 10 = secure. 6 to 8 = nearly there, revise the parts you missed. Under 6 = work through the lesson again with a grown-up.
Printable worksheet
- What is an investigation?
- What do we change?
- What do we measure?
- Why repeat?
- What do we conclude from?
- Why keep the ramp the same?
- Why graph results?
- Why link to friction?
- Plan an investigation.
- Run it.
Homework
Design a force test at home and explain what you would change and measure.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| 1. What is an investigation? | Planned test. | 1 |
| 2. What do we change? | Independent variable. | 1 |
| 3. What do we measure? | Dependent variable. | 1 |
| 4. Why repeat? | More reliable. | 1 |
| 5. What do we conclude from? | Evidence. | 1 |
| 6. Why keep the ramp the same? | Fair test. | 1 |
| 7. Why graph results? | See pattern. | 1 |
| 8. Why link to friction? | Explain. | 1 |
| 9. Plan an investigation. | Plan. | 1 |
| 10. Run it. | Table. | 1 |
| Total | 10 |
Independent practice answers. Level 1: 1 Planned test.; 2 Independent variable.; 3 Dependent variable.; 4 More reliable.; 5 Evidence.. Level 2: 1 Fair test.; 2 See pattern.; 3 Explain.. Level 3: 1 Plan.; 2 Table.; 3 Paragraph..
Quiz answers: 1 B, 2 C, 3 A, 4 B, 5 C, 6 A, 7 B, 8 C, 9 A, 10 B, 11 C, 12 A, Challenge 1 B, Challenge 2 C.
Mastery and remediation
| Objective | Bronze (Developing) | Silver (Proficient) | Gold (Advanced) |
|---|---|---|---|
| O1 Ask a testable question | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O2 Plan a fair test | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O3 Collect and graph data | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O4 Draw a conclusion about forces | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
Courseversity badge thresholds (overall quiz score): Gold = 90–100%; Silver = 80–89.9%; Bronze = 70–79.9%. A badge is never a full record of progress.
If a learner struggles
- Find the misconception: “Change everything at once.” Change one.
- Explain another way: use real objects, pictures or actions first, then words.
- Show a simpler example: Plan, run and report a force investigation.
- Guided practice: work through one example together and let the learner try the next one.
- Reassess: use the quiz again or the worksheet.
- Move on when the learner shows Silver-level evidence independently.
For parents and guardians
In this lesson your child plans and runs a force investigation. You do not need to be an expert to help.
- Help plan a test.
- Ask, “Is it fair?”
- Keep ramps low.
- Ask “how do you know?” after each answer, and listen.
- Praise effort, not only right answers. Mistakes are how we learn.
- Ten to fifteen minutes a day is better than one long session.
Teacher package
1–5. Objectives, prerequisites, materials, preparation, duration
Lesson objectives. Learners will: ask a testable question; plan a fair test; collect and graph data; draw a conclusion about forces.
Prerequisite knowledge. Grade 2 force ideas: pushes and pulls, simple machines and how forces change movement.
Materials. Boards, books, toy cars, rulers, surfaces. Low-resource options: use chalk or charcoal on a board or wall, drawings in the sand, and objects from the classroom instead of printed materials.
Preparation. Prepare ramps.
Suggested duration. 45–60 minutes. It can be split into two shorter sessions.
6–9. Teaching procedure, explanation notes, guided and independent activities
Introduction (5 min). Ask, “What could we test about forces?”
Explanation (10 min). Plan together.
Guided activity (10 min). Learners test.
Independent activity (10 min). Learners report.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. What did you change? What did you measure?
Teacher explanation notes. Start with real objects and safe, hands-on observation. Then talk about what was seen, then draw and write. Always say “how do you know?”. Keep to the safety notes, and use local, safe materials.
10–12. Differentiation, formative assessment, common misconceptions
Support. Use real objects and pictures, short sentences and a partner. Let learners point, show or draw instead of writing. Extension. Ask learners to find a new example at home and explain how they know.
Formative assessment. Listen to learners read and explain, ask “how do you know?”, and check the independent work.
Misconceptions. “Change everything at once.” Change one.
13–15. Assessment questions, answer keys, marking scheme
Use the quiz, the 10-mark exam practice and the worksheet on this page. All answers and marking guides are in the answer sections above. Re-check every answer before use.
16–19. Remediation, enrichment, homework, teacher reflection
Remediation. Plan, run and report a force investigation. Enrichment. Look for one new example near your home or school, draw it and explain it to someone. Homework. See above.
Teacher reflection. After teaching, record: which ideas learners understood; which misconceptions occurred; which activities worked; which learners need more practice; and what to improve next time.
Sources and standards
This lesson is based on the sources below, and no official endorsement is claimed. Reference starting points: Next Generation Science Standards, Cambridge Primary Science and the IB Primary Years Programme. Where a standard code is named, it points to the official framework.
Research used to shape this lesson. Courseversity Science curriculum, Grade 3 Unit 6, topic 10; Next Generation Science Standards, forces and interactions; Cambridge Primary Science Stage 3, forces and magnets; IB Primary Years Programme, how the world works. These sources informed the lesson.