You will learn
- Plan a fair test.
- Control variables.
- Record results.
- Test safely.
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.
- Control variables.
- Repeat at least three times.
- Record results in a table.
Words to know
a test that changes only one variable
something that can change
do again to check reliability
gives similar results each time
1. Discover: The same drop, every time
Two groups test egg carriers. One drops from 0.5 m, the other from 1 m, so they cannot compare results. “We must use the same height and the same floor,” says Ms Okyere. They test again, three times each, and record every result.
Think: Which variable did they need to control?
2. Understand: Testing
Idea 1: Fair
A fair test changes one variable and keeps the others the same. If we test two designs, the drop height, surface and load must match.
Idea 2: Reliable
Repeat each test at least three times and calculate the mean. If the results are close, the test is reliable.
Idea 3: Recording
Draw a results table before testing with a column for each trial and the mean. Record exactly what you measure with units, even when the result is disappointing.
3. Worked examples
Example 1 (I show you): Identify
Variables.
- Change.
- Measure.
- Keep.
Answer: Control.
Example 2 (We do it together): Calculate
Mean.
- Trial 1.
- Trial 2.
- Trial 3.
Answer: Average.
Example 3 (You try): Judge
Reliability.
Show the steps and answer
- Close.
- Spread.
- Repeat.
Answer: Reliable.
Did you know?
Car makers crash-test cars many times with identical dummies to check that the results are reliable.
Why this matters
Testing tells us whether the design works and shows how to improve it.
4. Explore: Load test
Test your prototype with identical small loads (such as 100 g masses) added one at a time, record the load at which it fails or bends, repeat three times and calculate the mean.
- Draw a table.
- Add loads.
- Repeat.
- Calculate.
Think about it: what did you notice?
What did you notice? The three trials gave similar results, so the test was reliable.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- A ___ test changes only one variable.
- A ___ is something that can change.
- To ___ is to do again.
- A ___ test gives similar results each time.
Guided practice
Question 1. Fair test?
One variable.
Question 2. Variable?
Can change.
Question 3. How many repeats?
Three.
Independent practice
Level 1: Start
- Fair test?
- Variable?
- How many repeats?
- Mean?
- Reliable?
Level 2: Grow
- Why control?
- Why repeat?
- Why record?
Level 3: Stretch
- Test.
- Mean.
- Judge.
Answers are in the answer key below. Try first, then check.
6. Apply: Science in everyday life
Explain why we repeat tests.
Show a sample answer
Give an example.
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.
Fix: One only.
8. Lesson summary and revision card
- I can plan a fair test.
- I can control variables.
- I can record results.
- I can test safely.
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.
- Control variables.
- Repeat at least three times.
- Record results in a table.
11. Next lesson
Next lesson: Analysing performance. 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.
- Define fair test and reliable. [2 marks]
- Plan a fair test. [3 marks]
- Calculate and interpret a mean. [3 marks]
- Safety rule. [2 marks]
Total: 10 marks.
Marking guide and model answers
- 1 each
- One variable [1]; controls [1]; repeats [1]
- Sum [1]; divide [1]; interpretation [1]
- Any [1]; reason [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
- Fair test?
- Variable?
- How many repeats?
- Mean?
- Reliable?
- Why control?
- Why repeat?
- Why record?
- Test.
- Mean.
Homework
Predict your prototype’s test result and explain.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| 1. Fair test? | One variable. | 1 |
| 2. Variable? | Can change. | 1 |
| 3. How many repeats? | Three. | 1 |
| 4. Mean? | Average. | 1 |
| 5. Reliable? | Consistent. | 1 |
| 6. Why control? | Fair. | 1 |
| 7. Why repeat? | Reliability. | 1 |
| 8. Why record? | Evidence. | 1 |
| 9. Test. | Table. | 1 |
| 10. Mean. | Number. | 1 |
| Total | 10 |
Independent practice answers. Level 1: 1 One variable.; 2 Can change.; 3 Three.; 4 Average.; 5 Consistent.. Level 2: 1 Fair.; 2 Reliability.; 3 Evidence.. Level 3: 1 Table.; 2 Number.; 3 Sentence..
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 | 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 Control variables | 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 results | 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 Test safely | 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.
- Explain another way: use real objects, pictures or actions first, then words.
- Show a simpler example: Test fairly.
- 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 safely and fairly. You do not need to be an expert to help.
- Watch a test.
- Ask “Was it fair?”
- Keep feet clear.
- 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; control variables; record results; test safely.
Prerequisite knowledge. Grade 5 ideas: the engineering design process, testing and improving a solution.
Materials. Masses, tray, ruler. 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 results 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). Drop two carriers from different heights and ask, “Is that fair?”
Explanation (10 min). Teach testing.
Guided activity (10 min). Learners test.
Independent activity (10 min). Learners calculate.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. What stays the same? How many trials?
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.
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. 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 6 Unit 11, topic 7; Next Generation Science Standards, engineering design; Cambridge Lower Secondary Science, thinking and working scientifically; IB Primary Years Programme, how we organise ourselves. These sources informed the lesson.