Practical Work Index | The Science Department

Required practicals for GCSE Science

Practical work helps you understand scientific ideas, develop investigative skills and apply what you know in examinations. Explore the required practicals for AQA GCSE Combined Science: Trilogy below.

Each practical includes guidance for carrying out the investigation and preparing for questions about practical techniques and results.

The paper shown on each card is taken from the practical database. Practical skills can also be assessed in unfamiliar contexts across GCSE Science.

Biology required practicals

Chemistry required practicals

Physics required practicals

Key language in practical science

These terms are important when planning investigations, interpreting results and answering practical examination questions. Make sure you can use them in familiar and unfamiliar investigations.

Word / Term Explanation
Independent Variable The single variable that you are changing (plotted on the x-axis)
Dependent Variable This is the variable that you are measuring during the experiment (plotted on the y-axis)
Control Variable These are the variable that you keep constant throughout the experiment
Continuous Variable Variables that are measured in numbers. They can get larger, smaller, negative or different intervals
Categoric Variable Varibles that have names such as colours or types of plant
Accuracy How close it is to the true value
Error or Uncertainty The range in which the true value can be found
Measurement Error Difference between the actual answer and that which you measured
Anomalies Results that are not a part of the pattern or trend (Do not include these when calculating a mean)
Random Error Natural spread of results when measuring, this can be reduced by calculating a mean
Systematic Error Errors consistently caused by an outside influence such as the same person reading the volume in a measuring cylinder from the wrong angle
Zero Error An error caused by the equipment not returning to zero such as a balance or a voltmeter
Fair Test The only variable changed is the Independent Variable
Interval The "distance" between your measurements
Range The "distance" between the highest and lowest measurement
Repeatable If the experiment is done again to the same method and gets the same result, it is repeatable
Reproducible If the experiment is repeated by another person or with different equipment and gets the same result, it is reproducible
Resolution The smallest degree to which you are measuring. IF you have 5.76g, the resolution is 0.01g
Validity A valid experiment has all of the controls in place, is a fair test and its proceedure is perfectly suitable

This page was updated on: 7th June 2026