Stage: 2 Challenge Level: 
Think of the properties of each of the numbers in turn.
Remember that each number can be in more than one set.
Factors and multiples. Divisibility. Combinations. Working systematically. Investigations. Multiplication & division. Comparing and Ordering numbers. Sequences. Odd and even numbers. Addition & subtraction.
Published March 2005,April 2005,November 2009,December 2009.
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