Aneasy activity might be to give each of your "students" a 10 X 10 table that contains all of the numbers from 1 to 100.

Then have them use the "Sieve of Erastothenes" method to colour in any number that is not a prime.

Once they have finished (gone through all numbers up to 100), you can talk about the numbers that haven't been coloured only being able to be divided by 1 and itself - and these numbers are called "Prime".

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