What is an ISA?

1. What is an ISA? • An ISA is a controlled assessment. • It tests your science skills. • You need to complete one for each GCSE in science that you do. The ISA counts 25% towards that GCSE.

2. Levels of Control • Limited Control: Candidates can work unsupervised and outside of the classroom. Candidates will carry out practical work under supervision. • High Control: Candidates work individually to complete their reports under conditions of high control at the centre and under direct, formal supervision.

3. What is in an isa? • Each ISA takes approximately 7 lessons to complete. • It includes practical and written assessments in the form of two exam papers.

4. Key Terms

5. Precision Precise Measurements are ones in which there is very little spread about the mean value.

6. Prediction A prediction is a statement suggesting what will happen in the future, based on observation, experience or a hypothesis.

7. Range The minimum and maximum values of the IV and/or DV.

8. Repeatable A measurement is repeatable if the experimenter can use the same method and equipment and obtain the same result

9. Reproducible A measurement is reproducible if the investigation is repeated by a different person and the same results are obtained.

10. Resolution The smallest change in the quantity being measured of a measuring instrument.

11. Sketch Graph A line graph, not necessarily on a grid, showing the relationship between two variables. No plots or scales used, but line of best fit drawn and axes labelled.

12. Uncertainty Results not quite where they are expected to be, which can be attributed to a problem with the method.

13. Control Variable (CV) A variable which is kept constant so that it does not affect the outcome of the investigation.

14. Independent Variable (IV) The variable that has values changed or selected by the experimenter.

15. Dependent Variable (DV) The variable that is measured for each and every change of the IV.

16. Accuracy An accurate measurement is considered to be close to the true value

17. Variables These are physical, chemical or biological quantities or characteristics

18. Categoric Variable Categoric variables are labels. For instance, type of material, brand of shoe or name of plant.

19. Continuous Variable A variable that can have a quantity (a number).

20. Calibration Setting the scales to zero.

21. Measurement Error The difference between a measured value and the true value

22. Systematic Error Measurements that differ from the true value by a consistent amount. Caused by the method used, equipment or the environment.

23. Random Error Cause readings to unpredictably spread about the true value. Reduced by repeat measurements and the calculation of the mean.

24. Zero Error Any indication that a measuring instrument gives a false reading when the true value of a quantity is zero.

25. Anomalies These are values in a set of results that are not judged to be part of the overall pattern.

26. Interval The quantity between readings. (e.g. Six readings equally spaced between 0 and 50cm would give an interval of 10cm)