Here you will find some more upper primary 'hidden gems' from NRICH, which we have selected as part of our feature to celebrate NRICH's 20th birthday.
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problem
Always, sometimes or never? Number
Are these statements always true, sometimes true or never true?
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problem
Sets of numbers
How many different sets of numbers with at least four members can you find in the numbers in this box?
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problem
Polygonals
Polygonal numbers are those that are arranged in shapes as they enlarge. Explore the polygonal numbers drawn here.