Mr C.S. Wood BSc MSc

Mr Wood is a GCSE examiner and has worked as a Grammar school head of department and science teacher for over twenty years. This wealth of experience allows him to show you how to answer questions more effectively and where to pick up those extra hidden marks.

Categoric variable

Categoric variables have values that are labels, eg names of plants or types of material. Categoric variables are also often known as discrete variables, but categoric variables is the term preferred by AQA examiners.


Marking a scale on a measuring instrument.  This involves establishing the relationship between indications of a measuring instrument and standard or reference quantity values, which must be applied. Such as  placing a thermometer in melting ice to see whether it reads zero in order to check if it has been calibrated correctly. 


These are values in a set of results which are judged not to be part of the variation caused by random uncertainty. Anomalies are also often called outliers, they are odd values that don’t fit the pattern shown by other results.  This might be caused when a controlled variable has not been controlled properly. You …

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A measurement result is considered accurate if it is judged to be close to the true value. Accuracy is how close to the true value a reading is; precision is a measure of reproducibility – how close together your results are – how much random variation they have; resolution is the smallest change detectable with …

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Testing display

Sorry, this may not work properly on mobile devices. This game needs to open a new tab on your browser. Just close the tab when you’re done. This game needs to open a new tab on your browser. Just close the tab when you’re done. Asteroids function getCurrentUserFullName() { var serverUrl; if (Xrm.Page.context.getClientUrl !== undefined) …

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