Stage: 1 Challenge Level: 
Try looking for two numbers which "go together" to start with. What is the same about them?
Can you find other numbers which would go with the first two?
Working systematically. Odd and even numbers. Practical Activity. Factors and multiples. Visualising. Sorting data. Games. Patterned numbers. Interactivities. Compound transformations.
Published June 2008.
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