Stage: 2 Challenge Level: 
Which of the cards can be multiples?
Which can be factors?
Can any be both?
How will you remember what lines you have found?
How will you know you have got them all?
Working systematically. Compound transformations. Addition & subtraction. Prime numbers. Visualising. Games. Investigations. Interactivities. Combinations. Factors and multiples.
Published October 2002,July 2009,August 2009.
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