HSC Science practical skills guide

Science exams often test how well you think like an investigator, not just whether you memorised content.

Variables

Identify the independent variable, dependent variable and controlled variables. Then explain why the controls matter. Higher-quality answers connect controls to validity, not just fairness.

Validity, reliability and accuracy

• Validity: does the method test what it claims to test?
• Reliability: would repeated trials produce consistent results?
• Accuracy: how close is the measurement to the true value?

Data interpretation

Do not only describe the trend. Explain what the trend suggests, identify anomalies and connect the data to scientific concepts. If a question asks you to assess data, mention limitations.

Experimental improvement answers

A weak improvement says “repeat the experiment”. A stronger answer says what to repeat, how many times, what average to calculate and how this improves reliability.