Stage: 1 Challenge Level: 
How could you group twenty sweets into fives?
How many sweets would you have had altogether if there were two left over after each of these groupings?
Odd and even numbers. Interactivities. Trial and improvement. Investigations. Multiplication & division. Addition & subtraction. Working systematically. Generalising. Factors and multiples. Prime numbers.
Published October 2002.
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