Year 7 · Questions, explanations and predictions

Learn the idea

A scientific question identifies something that observations or measurements could help answer. State what will be compared and how the outcome will be recognised. A broad word such as best needs a chosen measure before it becomes a useful investigation. Some questions about values or preferences have no single scientific verdict.

Observation, explanation and evidence

An observation records what is noticed or measured. An inference is an explanation drawn from observations, rather than a direct observation itself. Evidence is the observations and measurements used to judge an idea. Keep an original record and separate it from a possible explanation so another person can check the reasoning.

Make a reasoned prediction

A prediction states what you expect before checking the outcome. Add a scientific reason: I expect this change because this process should have that effect. A hypothesis is a proposed explanation that can be tested; a prediction follows from an explanation or model. Neither becomes a recorded result just because it sounds convincing.

Testability has limits

An experiment is one way to gather evidence; careful observations of things that cannot be changed by a learner can also be scientific. A question may be testable in principle but unsuitable or unsafe for a classroom. Use supplied data or simulations here, and revise an explanation when the evidence conflicts with it.

A ramp question

The fictional task asks how a toy car’s starting ramp height affects the distance it travels on the same floor. Height and stopping distance can be measured in centimetres. The wording identifies a comparison and an outcome; which car is nicest does not set a measurement rule for scientific testing.

Predict with a reason

A reasonable starting prediction is that the same car released from a greater height will travel farther under the same conditions, because more stored gravitational energy can be transferred. This is a proposed pattern for a limited model, not a guarantee for every car, height or floor. No physical ramp trial is required here.

A record is different from a guess

If the supplied result says 32 cm, record 32 cm even if the prediction was 30 cm. The observed value is 2 cm farther in this example. That difference calls for comparison and checking; it is not permission to alter the record or to declare the whole explanation universally true or false from one attempt.

Improve an unclear question

Replace Does a ramp work best? with How does ramp height affect stopping distance for the same model car on this surface? Then choose obtainable evidence and relevant conditions. Preference questions can be studied as stated preferences, but a vote does not reveal a scientifically best car for every purpose.

Common mistake

The scientifically useful question names evidence; adding the word science to a preference does not supply a measurement rule.

A revised prediction

A new prediction after reviewing evidence should be dated or labelled as revised while the original remains visible.

Another context

A virtual paper-strip test can compare bending in millimetres. It tests that stated property, not every possible meaning of strong.

Your written practice

Show your working on paper and enter your answer here. If it does not match, compare the model and try again.