Science · Unit 9

The Scientific Method

How scientists ask questions and test ideas

The method is not a ritual to be recited but a way of making sure a result means what you think it means. Its whole purpose is to rule out the explanations you would prefer.

The unit covers turning a question into a testable one, forming a hypothesis, identifying variables and keeping a test fair, running the experiment, and drawing a conclusion the data actually supports.

This unit breaks down into 22 short steps and 131 questions, starting at difficulty 2 and building to 4. Below you can see exactly what it covers, how the path is structured, and worked examples with explanations.

Steps: 22
Questions: 131
Difficulty: 2-4

What this unit covers

Asking a Testable Question
Doing the Experiment
Results and Conclusions
Variables and Fair Tests
Making a Hypothesis

Where this fits

Worth doing before Data, Graphs and Evidence and before Research Methods and Statistics.

Where people slip

A hypothesis that cannot fail is not a hypothesis. If no possible result would count against it, testing it tells you nothing.

How the unit is structured

The Scientific Method runs as 22 short steps that unlock in order. 16 are practice rounds and 6 are challenge rounds that pull together everything before them. Questions start at difficulty 2 and climb to 4 as you progress.

Step 1 · easierStep 22 · harder

Challenge rounds

Example questions

30 real questions from this unit, with the answer and the reason behind it, grouped by what they practise. There are 131 in the unit altogether.

Asking a Testable Question

Build the sentenceLevel 2
1. Build a sentence about how science begins.
Answer: Scientists start with a question they can test
Science usually begins with a clear question that can actually be tested.
Choose all that applyLevel 2
2. Which are features of a good scientific question? Pick all that apply.
- It focuses on one clear ideacorrect
- It can be measured or observedcorrect
- It can be tested with an experimentcorrect
- It is based only on personal taste
Good scientific questions are clear, measurable, and testable, not based on opinion.
Fact or fibLevel 2
3. The question 'Is summer the best season for a holiday?' can be settled by a scientific experiment.
Answer: False
The best season is a matter of opinion, so no measurement can answer it.
Fill the blankLevel 2
4. A testable question is one you can investigate by doing an ____.
- experimentcorrect
- opinion
- argument
- wish
Testable questions can be explored through experiments that produce real evidence.
Multiple choiceLevel 2
5. Which of these is a testable scientific question?
- Does the amount of sunlight change how tall a bean plant grows?correct
- Which flower is the prettiest?
- Should everyone learn to garden?
- Is autumn the best season?
A testable question can be answered by an experiment that measures something, like plant height.
Odd one outLevel 2
6. Which of these is NOT a testable scientific question?
- Which type of music is the most beautiful?correct
- Does temperature affect how fast sugar dissolves?
- Does fertilizer change how fast a plant grows?
- Does the surface affect how far a toy car rolls?
Beauty is a matter of opinion, so it cannot be tested or measured in an experiment.

Doing the Experiment

Choose all that applyLevel 2
7. Which are good practices while doing an experiment? Pick all that apply.
- Measure carefully each timecorrect
- Record data right awaycorrect
- Keep conditions consistentcorrect
- Guess the results without measuring
Careful measuring, prompt recording, and steady conditions all make results trustworthy.
Fact or fibLevel 2
8. Recording your measurements as you go is more reliable than trying to remember them later.
Answer: True
Writing data down immediately avoids memory mistakes and keeps your results accurate.
Fill the blankLevel 2
9. A ____ group does not receive the thing being tested, giving a baseline to compare against.
- controlcorrect
- random
- data
- variable
The control group shows what happens with no change, so you can compare it to the test group.
Guess the numberLevel 2
10. As a common minimum, how many times should you repeat a trial to get reliable data?
Answer: 3 times
Repeating at least three times helps you spot odd results and find a dependable average.
Match the pairsLevel 2
11. Match each thing you want to measure to the best tool for the job.
Answer: How long a reaction takes = Stopwatch; The mass of a sample = Balance; The temperature of water = Thermometer; The volume of a liquid = Measuring cylinder
Choosing the correct tool gives accurate, useful measurements.
Multiple choiceLevel 2
12. Why do scientists repeat an experiment several times?
- To check the results are consistent and reduce the effect of chancecorrect
- To use up extra materials
- To make the work take longer
- So they can change the answer they want
Repeating trials shows whether results are reliable and not just a one-time fluke.

Making a Hypothesis

Choose all that applyLevel 2
13. What makes a strong hypothesis? Pick all that apply.
- It is based on observations or prior knowledgecorrect
- It can be testedcorrect
- It makes a clear predictioncorrect
- It can never possibly be wrong
Strong hypotheses are informed, testable, and predictive, not impossible to disprove.
Fact or fibLevel 2
14. A good hypothesis can be tested and could be shown to be wrong.
Answer: True
Being testable means the evidence could either support or disprove the hypothesis.
Fill the blankLevel 2
15. Scientists often write a hypothesis like this: 'If I add fertilizer, ____ the plant will grow taller.'
- thencorrect
- maybe
- because
- never
The 'if... then...' form links what you change to what you predict will happen.
Multiple choiceLevel 2
16. What is a hypothesis?
- A testable, proposed explanation or prediction
- A fact that has already been proven
- The final conclusion of an experiment
- A wild guess with no reasoning
A hypothesis is a testable idea you propose before experimenting, based on what you already know.
Build the sentenceLevel 3
17. Build a hypothesis by arranging the words in order.
Answer: If the water is warmer then sugar dissolves faster
A clear hypothesis links a change (warmer water) to a predicted, measurable result (sugar dissolves faster).
Match the pairsLevel 4
18. Match each science term to its meaning.
Answer: Hypothesis = A testable proposed explanation; Theory = A well-supported explanation of many observations; Prediction = The specific result you expect to see; Observation = Something you notice using senses or tools
A hypothesis is a testable idea, a theory is broad and well-supported, a prediction states an expected result, and an observation is what you notice.

Results and Conclusions

Choose all that applyLevel 2
19. A trustworthy conclusion should have which qualities? Pick all that apply.
- It is supported by the datacorrect
- It stays honest even if the hypothesis was wrongcorrect
- It can be repeated by otherscorrect
- It matches whatever you wished would happen
Good conclusions are evidence-based, honest, and repeatable, not based on wishful thinking.
Fill the blankLevel 2
20. When the results match your prediction, we say the data ____ the hypothesis.
- supportcorrect
- disprove
- ignore
- hide
Data that matches the prediction supports the hypothesis, though it does not prove it forever.
Match the pairsLevel 2
21. Match each result to what it tells you.
Answer: Data matches the prediction = Hypothesis supported; Data does not match the prediction = Hypothesis not supported; Results are similar every trial = Data is reliable; Results vary wildly each trial = Data is not reliable
Matching results support a hypothesis, and consistent trials show the data is reliable.
Multiple choiceLevel 2
22. A conclusion should be based mainly on what?
- The data and evidence you collectedcorrect
- What you hoped would happen
- The most popular opinion
- A lucky guess
A good conclusion is drawn from the actual evidence, not from wishes or opinions.
Fact or fibLevel 3
23. A trustworthy scientific result should be reproducible by other scientists who repeat the experiment.
Answer: True
Reproducibility by independent scientists is a key sign that a result is trustworthy.
Guess the numberLevel 3
24. Three trials give plant heights of 8, 10, and 12 cm. What is the average (mean) height in cm?
Answer: 10 cm
Add the values (8 + 10 + 12 = 30) and divide by 3 to get an average of 10 cm.

Variables and Fair Tests

Build the sentenceLevel 2
25. Build the rule for controlling a fair test.
Answer: Keep all other conditions the same
Controlling the other conditions makes sure only the tested variable can matter.
Fill the blankLevel 2
26. The variable you deliberately change in an experiment is called the ____ variable.
- independentcorrect
- dependent
- controlled
- random
The independent variable is the one you choose to change on purpose.
Guess the numberLevel 2
27. In a fair test, how many variables should you change at one time?
Answer: 1 variable
Changing only one variable at a time lets you know what caused any change you see.
Match the pairsLevel 2
28. Match each type of variable to what it means.
Answer: Independent variable = The one you change; Dependent variable = The one you measure; Controlled variable = The one you keep the same
You change the independent variable, measure the dependent variable, and keep controlled variables constant.
Multiple choiceLevel 2
29. A student tests whether more fertilizer makes tomato plants taller. What is the independent variable?
- The amount of fertilizercorrect
- The height of the plants
- The type of pot used
- The amount of water given
The independent variable is the amount of fertilizer, because that is what the student changes.
Choose all that applyLevel 3
30. Which of these help make a test fair? Pick all that apply.
- Change only one variable at a timecorrect
- Keep all other conditions the samecorrect
- Measure the result the same way each timecorrect
- Change several things at once
A fair test changes one variable, controls the rest, and measures consistently.

Where these questions come from. Each unit starts as a plan of the concepts it should cover and the difficulty it should span. Questions are written against that plan with AI assistance, then checked by a validator that rejects anything without a single defensible answer, an explanation, or plausible wrong options. How we write questions sets out the whole process, and corrections are fixed in the bank and reach the site and the app the same day.

How you practise

This unit mixes 14 different question formats, so you are recalling and applying rather than recognising the same layout every time.

Build the sentence
Choose all that apply
Fact or fib
Fill the blank
Guess the number
Match the pairs
Multiple choice
Odd one out
Picture question
Put in order
Sort into groups
Spell it
True or false
Type the answer

Practise The Scientific Method

131 questions across 22 steps. Start with step one and crawl at your own pace.

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Read about The Scientific Method

Explainers from our blog on what this unit covers. Each one ends with real questions from the bank.

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