Have you tried this Earthlearningidea? 'Make your own rock' is an activity in which pupils investigate how loose sediment may be stuck together to form a 'rock'. To become hard rocks, most sediments need to be cemented together. Pupils will be able to demonstrate how 'rocks' are made by compacting and cementing loose sand, devise a fair way of testing the strength of their 'rocks' and be able to explain that the strength of the rock may depend as much on the cement that holds the particles together, as it does on the composition of the particles themselves.
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