Science Inquiry Skills: Designing and Interpreting Investigations
What you must understand
Inquiry skills cover the full arc of an investigation: formulating a testable question, writing a hypothesis that predicts a relationship, identifying independent, dependent and controlled variables, selecting appropriate measurement and sampling methods, managing risk, analysing data and drawing evidence-based conclusions. You must be able to read tables and graphs, describe trends, identify anomalies, discuss uncertainty and evaluate whether a conclusion is justified by the data.
Traps that appear in questions
- Confusing the independent variable with the control group; controls are treatments, variables are what you change or measure.
- Listing constants as variables. Controlled variables must be held constant and named specifically.
- Describing a trend without direction or magnitude ("it changed") instead of "increased steadily between 10 and 30 °C".
- Ignoring sample size, replication or randomisation when judging reliability.
- Confusing accuracy with precision, or reliability with validity.
- Drawing causal conclusions from correlational data.
Worked example and rule of thumb
A student measures enzyme activity at five temperatures with three replicates each. The dependent variable is rate of reaction, the independent variable is temperature, and constants include pH, substrate concentration and enzyme volume. If one replicate at 40 °C is far below the others, flag it as an anomaly, consider whether to exclude it with justification, and discuss possible causes. Rule of thumb: validity asks whether you measured the right thing; reliability asks whether repeated measurements agree; accuracy asks how close values are to the true value.