Stage: 1 Challenge Level: 
What number could you try first?
What else could you try?
How will you remember what you've found out?
What else could you try?
How will you remember what you've found out?
Addition & subtraction. Investigations. Divisibility. Odd and even numbers. Factors and multiples. Interactivities. Trial and improvement. Multiplication & division. Prime numbers. Working systematically.
Published December 2000.
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