These resources have been reviewed and selected by STEM Learning’s team of education specialists for factual accuracy and relevance to teaching STEM subjects in UK schools.


The video and worksheet set out a measurement challenge for students that can be carried out either at home or in school.  They can use a range of peeled and cut fruits and vegetable sticks submerged in water or salt solutions for fixed time periods to calculate the change in length that the effects of osmosis has had upon them. They are encouraged to to take multiple readings and use different varieties of fruit and vegetables and submit them to the NPL website, via a link in the worksheet. This resource could be used as a context to investigate the relationship between precision and resolution of the equipment used.

The report file looks at measurements taken by NPL and draws some conclusions.

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