You will learn
- Plan a fair test of a design.
- Repeat tests.
- Record measurements.
- Decide if criteria are met.
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
- Test against the criteria.
- Keep the test the same each time.
- Repeat to check results.
- Evidence shows what works.
Words to know
a trial to see how well something works
information collected from a test
to do a test again
a test where only one thing changes
1. Discover: The bridge test
Group D tests their card bridge. They place a toy car on it, then add coins one at a time. The bridge holds 18 coins. They repeat the test twice more: 17 and 18. “Our criteria said at least 15 coins,” says Adwoa. “We passed!”
Think: Why repeat the test?
2. Understand: Testing
Idea 1: Why test?
A test shows whether a design meets the criteria. Without testing we only guess. Testing gives evidence.
Idea 2: Fair testing
In a fair test only one thing changes. Use the same coins, the same place and the same method each time.
Idea 3: Repeat and record
Repeat the test at least three times and write every result. Similar results make us more confident.
3. Worked examples
Example 1 (I show you): Test
Add coins.
- One at a time.
- Count.
- Stop at failure.
Answer: Add load slowly and count.
Example 2 (We do it together): Repeat
18, 17, 18.
- Similar.
- Reliable.
- Three times.
Answer: Similar results are reliable.
Example 3 (You try): Check
Criteria 15.
Show the steps and answer
- 18 is more.
- Pass.
- Met.
Answer: The bridge meets the criteria.
Did you know?
Car makers crash-test vehicles many times so that engineers can make them safer.
Why this matters
Testing finds weaknesses before a design is used by real people.
4. Explore: Test the bridge
Test your model and record the result three times.
- Set up the test the same way.
- Add coins one at a time.
- Record the number held.
- Repeat three times.
Think about it: what did you notice?
What did you notice? Results were close each time.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- A ___ shows how well it works.
- ___ is information from a test.
- We ___ tests to check.
- In a ___ test only one thing changes.
Guided practice
Question 1. What is a test?
A trial.
Question 2. What is evidence?
Test information.
Question 3. What is repeating?
Do again.
Independent practice
Level 1: Start
- What is a test?
- What is evidence?
- What is repeating?
- What is a fair test?
- Why record?
Level 2: Grow
- Why repeat?
- Why fair?
- Why use criteria?
Level 3: Stretch
- Plan a test.
- Record three results.
- Does it meet the criteria?
Answers are in the answer key below. Try first, then check.
6. Apply: Science in everyday life
What would you test?
Show a sample answer
Model.
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: Repeat it.
Fix: Failures teach us.
8. Lesson summary and revision card
- I can plan a fair test of a design.
- I can repeat tests.
- I can record measurements.
- I can decide if criteria are met.
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
- Test against the criteria.
- Keep the test the same each time.
- Repeat to check results.
- Evidence shows what works.
11. Next lesson
Next lesson: Improving designs. 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.
- What is a fair test? [2 marks]
- Why repeat a test? [2 marks]
- Record three results in a table. [3 marks]
- Does a design meet criteria? [2 marks]
- Safety rule? [1 mark]
Total: 10 marks.
Marking guide and model answers
- One thing changes [1]; others same [1]
- Check results [1]; more reliable [1]
- Headings [1]; values [1]; units [1]
- Compare [1]; conclusion [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 a test?
- What is evidence?
- What is repeating?
- What is a fair test?
- Why record?
- Why repeat?
- Why fair?
- Why use criteria?
- Plan a test.
- Record three results.
Homework
Test a paper tower three times and record how many books it holds.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| 1. What is a test? | A trial. | 1 |
| 2. What is evidence? | Test information. | 1 |
| 3. What is repeating? | Do again. | 1 |
| 4. What is a fair test? | One change. | 1 |
| 5. Why record? | Keep results. | 1 |
| 6. Why repeat? | Check results. | 1 |
| 7. Why fair? | Trust results. | 1 |
| 8. Why use criteria? | Judge success. | 1 |
| 9. Plan a test. | Plan. | 1 |
| 10. Record three results. | Table. | 1 |
| Total | 10 |
Independent practice answers. Level 1: 1 A trial.; 2 Test information.; 3 Do again.; 4 One change.; 5 Keep results.. Level 2: 1 Check results.; 2 Trust results.; 3 Judge success.. Level 3: 1 Plan.; 2 Table.; 3 Statement..
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 Plan a fair test of a design | 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 Repeat tests | 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 Record measurements | 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 Decide if criteria are met | 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: “One test is enough.” Repeat it.
- Explain another way: use real objects, pictures or actions first, then words.
- Show a simpler example: Test fairly, repeat and record.
- 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 tests a design fairly. You do not need to be an expert to help.
- Test a paper tower together.
- Ask, “Was it fair?”
- Use light loads.
- 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: plan a fair test of a design; repeat tests; record measurements; decide if criteria are met.
Prerequisite knowledge. Grade 3 science ideas from earlier units: asking questions, fair tests, properties of materials, forces and recording results.
Materials. Card, coins, notebooks. 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 test tables.
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, “How do we know it works?”
Explanation (10 min). Teach fair testing.
Guided activity (10 min). Learners test.
Independent activity (10 min). Learners compare.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. Was it fair? Do results agree?
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. “One test is enough.” Repeat it.
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. Test fairly, repeat and record. 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 10, topic 6; Next Generation Science Standards, engineering design (developing solutions, optimizing); Cambridge Primary Science Stage 3, thinking and working scientifically; IB Primary Years Programme, how we organise ourselves and how the world works. These sources informed the lesson.